Clinical Characteristics, Radiological Findings, Treatment Patterns, and Prognostic Factors in Spinal Alveolar Soft Part Sarcoma: A Retrospective Study of 20 Patients

Clinical Characteristics, Radiological Findings, Treatment Patterns, and Prognostic Factors in Spinal Alveolar Soft Part Sarcoma: A Retrospective Study of 20 Patients | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Clinical Characteristics, Radiological Findings, Treatment Patterns, and Prognostic Factors in Spinal Alveolar Soft Part Sarcoma: A Retrospective Study of 20 Patients jian sun, Chenglong Zhao, Na Cui, Zhenhua Zhou, Haiyi Gong, Haocheng Zhu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9504084/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Background Spinal alveolar soft part sarcoma (ASPS) is exceptionally rare, and evidence regarding its optimal management remains limited. This study aimed to describe the clinical and radiological features of spinal ASPS, assess treatment patterns, and identify factors associated with overall survival. Methods We retrospectively reviewed 20 patients with spinal ASPS who underwent surgery at a single center between 2012 and 2023. Demographic, clinical, radiological, surgical, pathological, and adjuvant treatment data were collected. Survival was analyzed using the Kaplan–Meier method, and prognostic factors were evaluated using univariate and multivariate Cox regression analyses. Results The cohort included 17 males and 3 females, with a mean age of 33.95 years. Fourteen patients (70.0%) had metastatic disease, including 12 before surgery and 2 after surgery. All patients underwent posterior tumor resection and spinal reconstruction; 12 underwent en-bloc resection and 8 underwent subtotal resection. Mean intraoperative blood loss was 2400 mL, and 16 patients required transfusion. Early postoperative evaluation showed significant symptomatic or neurological improvement in 11 patients (55.0%), partial improvement in 4 (20.0%), stable or limited change in 4 (20.0%), and neurological deterioration in 1 (5.0%). During a mean follow-up of 33.15 months, 9 patients were alive and 11 had died. Median overall survival was 28.0 months. Univariate radiological analysis showed that tumor boundary clarity (P < 0.001), enhancement uniformity (P = 0.013), and T2-weighted signal intensity (P = 0.032) were significantly associated with prognosis. Multivariate analysis identified postoperative immunotherapy (HR = 0.092, P = 0.039) and better preoperative neurological status (Frankel grade D–E; HR = 0.079, P = 0.006) as independent protective factors, whereas en-bloc resection showed a favorable survival trend (HR = 0.236, P = 0.070). Conclusions Spinal ASPS is a highly vascular and surgically demanding malignancy with a substantial metastatic burden. Preoperative tissue diagnosis and selective embolization should be considered when appropriate. En-bloc resection may offer oncological benefit in selected patients, and postoperative immunotherapy was associated with improved survival in this cohort. Trial registration Not applicable. alveolar soft part sarcoma spine en-bloc resection immunotherapy prognosis overall survival Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Alveolar soft part sarcoma (ASPS) is a rare malignancy of uncertain origin that accounts for approximately 1% of soft tissue sarcomas and is classified as an ultra-rare sarcoma[ 1 ]. First described by Christopherson et al. in 1952[ 2 ], ASPS predominantly affects young adults aged 15 to 35 years, with a higher incidence in females before age 30 and in males thereafter[ 3 ]. Common primary sites include the lower extremities, trunk, and head and neck[ 4 ]. Rare primary sites have also been reported in the intestine, lung, uterus, intracranial region, tongue, and spleen[ 5 – 10 ]. According to the BSTTR database, approximately 72% of patients present with metastases, most commonly involving the lung, bone, brain, and liver[ 1 , 11 ]. Surgical resection remains the primary curative treatment modality[ 11 , 12 ]. Spinal ASPS is exceptionally rare and is often accompanied by marked neurological impairment, leading some authors to advocate aggressive surgical intervention[ 13 ]. However, spinal surgery carries substantial risk. The tumor's rich vascularity and locally destructive behavior complicate resection[ 14 ], and radical en-bloc excision is especially challenging because of the risk of massive hemorrhage and injury to critical neurovascular structures. At the molecular level, ASPS is characterized by the ASPSCR1::TFE3 fusion gene, which drives tumorigenesis and angiogenesis[ 15 ]. Radiologically, ASPS is typically hypervascular[ 16 , 17 ] and often demonstrates intratumoral flow-void signs[ 18 ], which helps explain its propensity for severe intraoperative bleeding. ASPS is generally insensitive to conventional chemotherapy[ 19 ], and the role of adjuvant radiotherapy remains controversial[ 4 ]. More recently, targeted therapy and immunotherapy have shown promise. VEGF-targeting tyrosine kinase inhibitors (TKIs) are biologically rational because of the angiogenic nature of ASPS[ 20 ], while the highly vascular tumor microenvironment may also facilitate immune infiltration and antigen presentation[ 21 ]. Atezolizumab monotherapy has achieved an objective response rate (ORR) of 37%[ 22 ], and PD-L1 blockade combined with TKIs has produced ORRs exceeding 80% with median progression-free survival (PFS) longer than 35 months[ 23 ]. Nonetheless, these data remain limited, and the prognosis of metastatic ASPS is still poor[ 13 ]. The rarity of spinal ASPS means that robust evidence on optimal surgery, perioperative care, adjuvant therapy, and prognostic factors is still lacking. We retrospectively analyzed 20 patients with spinal ASPS treated at our institution between January 1, 2012 and December 31, 2023. This study aimed to characterize their clinical features, surgical and perioperative characteristics, and radiological manifestations, to evaluate treatment efficacy, and to identify independent prognostic factors that may help guide clinical decision-making. Methods Patients Data were collected from patients with alveolar soft part sarcoma who underwent surgical treatment in the Department of Orthopedic Oncology at our institution between January 1, 2012 and December 31, 2023. All patients had a postoperative pathological diagnosis of ASPS. Inclusion criteria were as follows: (1) resection of a spinal lesion in our department; and (2) postoperative pathological confirmation of ASPS. Exclusion criteria were: (1) ASPS lesions located outside the spine (n = 9); (2) biopsy suggesting ASPS without subsequent surgical resection (n = 4); and (3) loss to follow-up (n = 2) (Fig. 1 ). The final cohort included 20 patients: 3 cervical, 7 thoracic, 7 lumbar, and 3 sacral cases. This retrospective cohort study was approved by the Medical Ethics Committee of Shanghai Changzheng Hospital (Approval No. 2018SL004). Written informed consent to participate was obtained from all patients or their legal guardians. Patient Characteristics Patient-related variables included sex, age, smoking history, symptoms, preoperative metastasis, Frankel grade, and Karnofsky Performance Status (KPS) score. Tumor-related variables included location, number of involved segments, tumor diameter, Ki-67 index, preoperative Epidural Spinal Cord Compression (ESCC) score, and Spinal Instability Neoplastic Score (SINS). Laboratory variables included preoperative erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), D-dimer, hemoglobin (Hb), albumin (ALB), and postoperative day 1 hemoglobin (POD1 Hb). Treatment-related variables included preoperative embolization, surgical strategy, adjuvant immunotherapy, and postoperative radiotherapy. Clinical records, surgical details, imaging examinations, and pathological findings were retrieved from the institutional database and hospital records. Overall survival events were calculated from the date of surgery to death or last follow-up through July 1, 2024. Patients were followed in the outpatient clinic at 3, 6, and 12 months postoperatively, every 6 months during the second postoperative year, and annually thereafter. Because many patients already had metastases before surgery, progression-free survival was difficult to assess reliably. Radiological Analysis Radiological data from CT and MRI were retrieved from patient archives. Imaging characteristics were evaluated by radiologists and included tumor location, size, boundaries, distant metastases, internal and peripheral structure, density/signal intensity, intratumoral flow voids, enhancement pattern, and extent of bone destruction. T1WI and T2WI signal intensity were interpreted relative to adjacent muscle signal on the corresponding sequence. Statistical Methods Data were analyzed using SPSS Statistics version 22.0 (IBM, New York, USA) and GraphPad Prism version 8.0.2 (GraphPad Software, California, USA). Categorical variables were compared using the chi-square test or Fisher’s exact test (two-tailed), as appropriate. Continuous variables were compared using parametric methods as appropriate. Overall survival (OS) was defined as the primary endpoint and was analyzed using the Kaplan–Meier method. Differences were assessed with the log-rank test. Variables with P < 0.1 on univariate analysis were entered into multivariate Cox regression using a backward selection method. A two-sided P value < 0.05 was considered statistically significant. Results Clinical Characteristics, Surgical Interventions, and Prognostic Outcomes A total of 20 patients who underwent surgery for spinal ASPS lesions were included in this study, comprising 17 males and 3 females, with a mean age of 33.95 years (range, 16–63 years). Fourteen patients (70.0%) had metastatic disease, including 12 with metastases before surgery and 2 who developed metastases after surgery. The most common metastatic sites were the skeletal system (including the spine, skull, and ribs; 12/14, 85.71%) and the lungs (10/14, 71.43%); one patient each had liver and brain metastases. Most patients presented with overlapping symptoms before surgery. Pain was the most common symptom and was documented in 10 patients, mainly involving the lumbosacral region, buttock, and upper or lower extremities. Motor dysfunction was present in 11 patients, including 9 with lower-extremity motor impairment: 4 with complete paraplegia, 3 with bilateral lower-extremity weakness, and 2 with unilateral lower-extremity paralysis or weakness. Some patients also had incomplete paresis of the upper extremities. Sensory disturbance or numbness was present in 4 patients, all involving the left upper and/or lower extremities. In 2 patients, the lesion was detected incidentally during physical examination. The main surgical indications in this cohort were neurological dysfunction caused by compression, intractable pain, increasing local tumor burden, and reconstruction of instability caused by osseous destruction (Table 1). All patients underwent posterior tumor resection and reconstruction. Among the 12 patients who underwent en-bloc resection, reconstruction was performed using pedicle screws plus titanium mesh in 9 cases and pedicle screws plus an artificial vertebral body in 3 cases. Among the 8 patients who underwent subtotal resection, reconstruction consisted of pedicle screws alone in 3 cases, pedicle screws plus titanium mesh in 2 cases, pedicle screws plus bone cement in 2 cases, and cement-augmented screws in 1 case. Seven patients underwent selective preoperative arterial embolization. The perioperative hematologic burden was substantial. Mean intraoperative blood loss for the entire cohort was 2400 mL (median, 1900 mL; range, 400–7000 mL). Stratified by surgical approach, the mean blood loss was 1950 mL in the en-bloc group and 3075 mL in the subtotal resection group. Sixteen patients required intraoperative transfusion; among these 16 patients, the mean transfusion volume was 2225 mL (median, 1700 mL; range, 400–5200 mL). Mean preoperative hemoglobin was 135.8 g/L and decreased to 102.5 g/L on postoperative day 1, corresponding to an average decline of approximately 33.4 g/L. Early postoperative clinical outcomes showed that 11 patients (55.0%) achieved significant symptom relief or neurological improvement, 4 patients (20.0%) experienced partial improvement (for example, pain or sensory improvement without definite motor recovery), 4 patients (20.0%) remained stable or showed only limited improvement, and 1 patient (5.0%) developed definite postoperative neurological deterioration. Three patients experienced documented perioperative complications: one had bilateral lower-extremity edema, severe systemic infection, and pleural effusion; one developed isolated pleural effusion; and one experienced dural injury with cerebrospinal fluid leakage. No patient died from perioperative complications. Postoperative adjuvant treatment included radiotherapy in 11 patients, immunotherapy in 8 patients, and targeted therapy in 7 patients. Postoperative pathology confirmed ASPS in all cases (Fig. 2 ). Immunohistochemical analysis of the surgical specimens (Fig. 3 ) showed that TFE3 nuclear positivity was the most frequent finding, present in 94.12% of tested cases (16/17), supporting its role as a key diagnostic marker. Other markers included Vimentin (66.67%, 10/15), PAS (90.00%, 9/10), MyoD1 (47.37%, 9/19), NSE (60.00%, 6/10), EMA (28.57%, 4/14), CK (pan) (15.79%, 3/19), S100 (16.67%, 3/18), and Desmin (18.75%, 3/16) (Supplementary Table 2). During a mean follow-up of 33.15 months (maximum, 120 months), 9 patients were alive and 11 had died by the last follow-up. Radiological Manifestations and Prognosis Among the 20 patients, 18 underwent MRI and 16 underwent CT of the spinal lesion planned for surgery. On MRI, 10 cases (55.56%) showed heterogeneous enhancement and 8 cases (44.44%) showed uniform enhancement. On T1-weighted images, 13 cases (72.22%) were hypointense and 5 cases (27.78%) were isointense. On T2-weighted images, 9 cases (50.00%) were hyperintense and 9 cases (50.00%) were isointense. Tumor boundaries were clear in 8 cases (44.4%) and unclear in 10 cases (55.6%). Flow voids were identified in 16 cases (88.89%). On CT, 12 of 16 cases (75.00%) showed osteolytic bone destruction and 4 of 16 cases (25.00%) showed osteoblastic destruction. All 16 lesions examined with contrast-enhanced CT showed definite enhancement (Supplementary Table 3). Univariate analysis of preoperative radiological factors (Table 2) showed that tumor boundary (clear vs blurred, P < 0.001), MRI enhancement pattern (uniform vs heterogeneous, P = 0.013), and T2WI signal intensity (isointense vs hyperintense, P = 0.032) were significantly associated with prognosis. T1WI signal intensity (P = 0.297), flow voids (P = 0.139), and CT bone destruction pattern (P = 0.280) were not statistically significant. Clinicopathological Features and Survival Analysis The 1-year OS rate after surgery for spinal ASPS was 70.0%, and the median OS was 28.0 months (95% CI, 7.6–48.4). We further evaluated the impact of clinicopathological variables on survival using univariate (Table 3) and multivariate (Table 4) analyses. Univariate analysis showed that elevated D-dimer (> 1 mg/L; P 10 mg/L; P = 0.001), and hypoalbuminemia (ALB < 40 g/L; P = 0.009) were associated with poorer prognosis. Functional status indicators were also important: preoperative neurological deficit (Frankel grade A–C; P < 0.001) and poorer performance status (KPS 10 mm/h; P = 0.015) were also adverse prognostic factors. At the treatment level, receiving immunotherapy (P = 0.007) and undergoing en-bloc resection (P = 0.045) were associated with longer survival. In contrast, age, sex, tumor size, number of involved segments, and Ki-67 index were not significantly associated with prognosis in this cohort. Multivariate Cox regression identified three variables of interest: postoperative immunotherapy (HR = 0.092, 95% CI 0.010–0.888; P = 0.039), preoperative Frankel grade D–E (HR = 0.079, 95% CI 0.013–0.490; P = 0.006), and en-bloc resection (HR = 0.236, 95% CI 0.049–1.127; P = 0.070) (Fig. 4 ). Immunotherapy and better preoperative neurological status were independent protective factors, whereas en-bloc resection showed a favorable trend that did not reach conventional statistical significance. Discussion ASPS is a rare mesenchymal neoplasm accounting for less than 1% of all sarcomas, with an estimated annual incidence of 1.2 per 10 million population[ 24 ]. Its defining genomic alteration is the t(X;17)(p11;q25) translocation, which fuses ASPSCR1 and TFE3 to generate the oncogenic ASPSCR1::TFE3 fusion protein[ 25 ]. In diagnostic practice, TFE3 immunohistochemistry has high sensitivity, generally exceeding 95%[ 26 ], which is consistent with the 94.12% positivity rate (16/17) observed in our cohort. TFE3 expression is also useful in differentiating ASPS from entities such as paraganglioma and granular cell tumor[ 27 ], and it has been recognized as a key diagnostic marker in multiple clinicopathologic studies[ 12 , 28 , 29 ]. The ASPSCR1::TFE3-driven angiogenic program renders ASPS highly hypervascular[ 30 – 32 ]. Although hypervascularity is not specific and can also be seen in other spinal sarcomas, its presence has important operational implications[ 33 ]. In our series, spinal ASPS most commonly appeared hypointense or slightly hypointense on T1-weighted imaging (72.22%), differing somewhat from previous reports of extremity ASPS, which more often appears isointense or slightly hyperintense[ 31 , 34 ]. ASPS is typically described as intermediate to high signal on T2-weighted imaging[ 17 ]; in our cohort, patients with isointense T2WI signals had better survival than those with hyperintense signals (P = 0.032). All tumors enhanced after contrast administration, and uniform enhancement (P = 0.013) as well as a clear tumor boundary (P < 0.001) were associated with a more favorable prognosis. These findings suggest that preoperative imaging may help estimate biological behavior and risk. Intraoperative blood loss in spinal ASPS was considerable, averaging 2400 mL and reaching 7000 mL in the most extreme case, which is markedly higher than the average blood loss reported for general oncologic spine surgery (approximately 1176 ± 1209 mL)[ 35 ]. In our cohort, 80.0% of patients required perioperative transfusion, with a mean transfusion volume of 2225 mL, and mean hemoglobin fell by more than 30 g/L on postoperative day 1. Although only 35.0% of patients underwent selective preoperative embolization, these findings strongly support routine preoperative pathologic confirmation, consideration of selective embolization, adequate blood preparation, and meticulous intraoperative hemostatic planning for spinal ASPS with imaging features suggestive of hypervascularity. For spinal ASPS, surgery is the mainstay of local control, but its risks and benefits must be weighed carefully. For soft tissue ASPS, complete resection is generally preferred whenever feasible[ 11 , 12 ]. However, because spinal ASPS is extremely uncommon, surgical indications are not well defined. Spinal surgery itself carries substantial risks, including neurologic injury, uncontrollable hemorrhage, and postoperative complications[ 36 – 38 ]. Current surgical principles for primary spinal sarcomas generally favor aggressive resection, particularly en bloc resection when feasible and oncologically appropriate[ 39 ]. For metastatic spinal disease, surgery is usually guided by expected survival: palliative surgery may be considered when life expectancy is at least 3 months[ 40 , 41 ], whereas en-bloc resection is generally reserved for selected patients with an anticipated survival of 12–24 months[ 42 , 43 ]. Our data suggest that patients treated with en-bloc resection tended to have better survival than those treated with piecemeal subtotal resection. In multivariate analysis, en-bloc resection showed a trend toward prolonged survival (HR = 0.236, 95% CI 0.049–1.127; P = 0.070), although statistical significance was not reached, likely because of the limited sample size. Importantly, this finding should be interpreted in the context of patient selection. In our cohort, the main drivers for surgery were neurologic compromise, intractable pain, local tumor burden, and the need to reconstruct spinal stability. Patients selected for en-bloc resection generally had more favorable tumor boundaries, better resectability, and better overall physiologic reserve. Therefore, the apparent survival advantage should not be attributed solely to the surgical technique itself, but rather interpreted within the broader framework of case selection and surgical feasibility. For advanced soft tissue sarcoma, systemic treatment has traditionally relied on cytotoxic chemotherapy[ 44 ], but chemotherapy is generally ineffective in ASPS[ 45 ]. ASPS is also often considered relatively radioresistant[ 46 ], and the value of radiotherapy remains debated[ 47 ]. Nevertheless, some authors support high-dose radiotherapy for selected settings such as brain metastases[ 48 ]. In our cohort, 11 patients received postoperative radiotherapy. Although radiotherapy was not associated with improved OS in this cohort, it may still have a role in selected patients, particularly for local control when recurrence would be clinically devastating. Recent studies have shown activity with tyrosine kinase inhibitors and immune checkpoint inhibitors in advanced ASPS. TKIs such as sunitinib and pazopanib have shown meaningful disease control in advanced ASPS[ 49 ], and ASPS is considered one of the sarcoma subtypes most likely to benefit from immune checkpoint inhibition[ 50 ]. Atezolizumab has induced durable responses in approximately one-third of patients with advanced ASPS[ 22 ]. VEGF signaling may also contribute to immune evasion[ 51 ], providing a rationale for combined anti-angiogenic and PD-1/PD-L1 blockade. In a phase II study of axitinib plus pembrolizumab in advanced sarcoma, 6 of 11 patients with ASPS achieved partial response and 2 achieved stable disease[ 52 ]. In our study, multivariate analysis identified postoperative immunotherapy as an independent protective factor for OS, supporting its role as an important component of postoperative systemic management. Although targeted therapy was not significantly associated with improved OS in this cohort, immunotherapy combined with targeted therapy remains a rational option for patients with unresectable disease or suboptimal surgical margins. With respect to prognostic markers, prior studies have focused mainly on tumor burden, primary site, metastatic status, and treatment modality[ 11 , 12 , 53 ]. Our data also highlight the importance of host status and inflammatory biomarkers. Elevated D-dimer and C-reactive protein, which may reflect hypercoagulability and systemic inflammation, and hypoalbuminemia, which may reflect poor nutritional reserve, were all associated with worse survival. These findings suggest that prognosis in spinal ASPS is influenced not only by tumor-related variables but also by systemic host condition. Together with the protective associations observed for immunotherapy and better preoperative neurologic status, these results support the view that prognosis in spinal ASPS is multidimensional rather than determined by a single factor. This study has several limitations. First, the sample size was small, with only 20 patients, which limits statistical power. Second, radiological data were incomplete for some patients, and diffusion-weighted imaging was not available, limiting comprehensive radiologic assessment. Third, because of the retrospective design, targeted therapy and immunotherapy were not standardized, and different drugs were used across patients. Larger prospective studies are needed to confirm these findings. Nonetheless, this study provides preliminary evidence supporting the clinical relevance of imaging features, surgical strategy, and immunotherapy in spinal ASPS. Conclusions Spinal ASPS is a rare, highly vascular malignancy that presents major surgical and oncological challenges. In this cohort, postoperative immunotherapy and better preoperative neurological status were independently associated with improved survival, while en-bloc resection showed a favorable but non-significant survival trend. Careful preoperative evaluation, including tissue diagnosis and consideration of selective embolization, may help optimize surgical planning. When technically feasible and compatible with neurological preservation, en-bloc resection remains a reasonable surgical goal. Given the rarity of the disease and the limitations of retrospective single-center data, larger multicenter studies are required to clarify the roles of surgery, radiotherapy, targeted therapy, and immunotherapy in the management of spinal ASPS. Abbreviations ASPS Alveolar soft part sarcoma ALB Albumin CRP C-reactive protein CT Computed tomography ESCC Epidural Spinal Cord Compression ESR Erythrocyte sedimentation rate Hb Hemoglobin KPS Karnofsky Performance Status MRI Magnetic resonance imaging ORR Objective response rate OS Overall survival PAS Periodic acid–Schiff PFS Progression-free survival POD1 Hb Postoperative day 1 hemoglobin SINS Spinal Instability Neoplastic Score TKI Tyrosine kinase inhibitor T1WI T1-weighted imaging T2WI T2-weighted imaging Declarations Ethics approval and consent to participate This research project was examined and approved by the Medical Ethics Committee of Shanghai Changzheng Hospital (Approval No. 2018SL004), and written informed consent was obtained from all patients or their legal guardians. Consent for publication Written informed consent was obtained from all patients for the publication of this study and any accompanying images. Availability of data and materials All data generated or analysed during this study are included in this published article and its supplementary information files. Competing interests The authors declare that they have no competing interests. Funding This study was supported by the National Natural Science Foundation of China (Grant Nos. 82372910 and 82273471), the Shanghai Orthopedic Research Center for Spinal Disorders and Traumatology (Grant No. 21MC1930100), and the Shanghai Municipal Science and Technology Commission Orthopedic Clinical Medical Research Center Construction Project (Grant No. 20222Z01013). The funding bodies had no role in the design of the study, data collection, analysis, interpretation of data, or writing of the manuscript. Authors’ contributions Z.W., T.W., and J.X. contributed to the study conception and design. Material preparation and data collection were performed by N.C. and J.S. Statistical analysis was performed by J.S. T.W., C.Z., Z.Z., H.G., H.Z., Z.W., and J.X. were responsible for the treatment of patients. The first draft of the manuscript was written by T.W. and J.S. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Acknowledgements Not applicable. Authors’ information J.S., C.Z., and N.C. contributed equally to this work and should be considered co-first authors. References Brahmi M, Vanacker H, Dufresne A. Novel therapeutic options for alveolar soft part sarcoma: antiangiogenic therapy, immunotherapy and beyond. Curr Opin Oncol. 2020;32:295–300. doi:10.1097/CCO.0000000000000652. Christopherson WM, Foote FW, Stewart FW. Alveolar soft-part sarcomas; structurally characteristic tumors of uncertain histogenesis. Cancer. 1952;5:100–11. doi:10.1002/1097-0142(195201)5:1%3C100::aid-cncr2820050112%3E3.0.co;2-k. Paoluzzi L, Maki RG. Diagnosis, Prognosis, and Treatment of Alveolar Soft-Part Sarcoma: A Review. 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Molecular Landscape in Alveolar Soft Part Sarcoma: Implications for Molecular Targeted Therapy. Biomed Pharmacother. 2018;103:889–96. doi:10.1016/j.biopha.2018.04.117. Wang S, Wang Y, Xu J, Ren Q, Hu Y, Jia L, et al. Ultrasound characteristics of alveolar soft part sarcoma in pediatric patients: a retrospective analysis. BMC Cancer. 2024;24:1484. doi:10.1186/s12885-024-13262-x. Gulati M, Mittal A, Barwad A, Pandey R, Rastogi S, Dhamija E. Imaging and Pathological Features of Alveolar Soft Part Sarcoma: Analysis of 16 Patients. Indian J Radiol Imaging. 2021;31:573–81. doi:10.1055/s-0041-1735501. Mcaddy NC, Saffar H, Litière S, Jespers P, Schöffski P, Messiou C. iCREATE: imaging features of primary and metastatic alveolar soft part sarcoma from the EORTC CREATE study. Cancer Imaging. 2020;20:79. doi:10.1186/s40644-020-00352-9. Ledoux P, Kind M, Le Loarer F, Stoeckle E, Italiano A, Tirode F, et al. Abnormal vascularization of soft-tissue sarcomas on conventional MRI: Diagnostic and prognostic values. Eur J Radiol. 2019;117:112–9. doi:10.1016/j.ejrad.2019.06.007. Yuan J, Xie D, Fang S, Meng F, Wu Y, Shan D, et al. Qualitative and quantitative MRI analysis of alveolar soft part sarcoma: correlation with histological grade and Ki-67 expression. Insights Imaging. 2024;15:142. doi:10.1186/s13244-024-01687-8. Mohme M, Mende KC, Pantel T, Viezens L, Westphal M, Eicker SO, et al. Intraoperative blood loss in oncological spine surgery. Neurosurg Focus. 2021;50:E14. doi:10.3171/2021.2.FOCUS201117. Swann MC, Hoes KS, Aoun SG, McDonagh DL. Postoperative complications of spine surgery. Best Pract Res Clin Anaesthesiol. 2016;30:103–20. doi:10.1016/j.bpa.2016.01.002. Anadio JM, Sturm PF, Forslund JM, Agarwal S, Lane A, Tarango C, et al. A bleeding assessment tool correlates with intraoperative blood loss in children and adolescents undergoing major spinal surgery. Thromb Res. 2017;152:82–6. doi:10.1016/j.thromres.2017.02.020. Ando K, Kobayashi K, Nakashima H, Machino M, Ito S, Kanbara S, et al. Surgical outcomes and factors related to postoperative motor and sensory deficits in resection for 244 cases of spinal schwannoma. J Clin Neurosci. 2020;81:6–11. doi:10.1016/j.jocn.2020.09.025. Yeung CM, Bilsky M, Boland PJ, Vaynrub M. The Role of En Bloc Resection in the Modern Era for Primary Spine Tumors. Spine (Phila Pa 1976). 2024;49:46–57. doi:10.1097/BRS.0000000000004821. Hammerberg KW. Surgical treatment of metastatic spine disease. Spine (Phila Pa 1976). 1992;17:1148–53. doi:10.1097/00007632-199210000-00004. Sundaresan N, Digiacinto GV, Hughes JE, Cafferty M, Vallejo A. Treatment of neoplastic spinal cord compression: results of a prospective study. Neurosurgery. 1991;29:645–50. doi:10.1097/00006123-199111000-00001. Tokuhashi Y, Matsuzaki H, Oda H, Oshima M, Ryu J. A revised scoring system for preoperative evaluation of metastatic spine tumor prognosis. Spine (Phila Pa 1976). 2005;30:2186–91. doi:10.1097/01.brs.0000180401.06919.a5. Kato S, Murakami H, Demura S, Yoshioka K, Yokogawa N, Yonezawa N, et al. Kidney and Thyroid Cancer-Specific Treatment Algorithm for Spinal Metastases: A Validation Study. World Neurosurg. 2019;122:e1305–11. doi:10.1016/j.wneu.2018.11.040. Gamboa AC, Gronchi A, Cardona K. Soft-tissue sarcoma in adults: An update on the current state of histiotype-specific management in an era of personalized medicine. CA Cancer J Clin. 2020;70:200–29. doi:10.3322/caac.21605. Liu J, Fan Z, Li S, Gao T, Xue R, Bai C, et al. Target therapy for metastatic alveolar soft part sarcoma: a retrospective study with 47 cases. Ann Transl Med. 2020;8:1493. doi:10.21037/atm-20-6377. Orbach D, Brennan B, Casanova M, Bergeron C, Mosseri V, Francotte N, et al. Paediatric and adolescent alveolar soft part sarcoma: A joint series from European cooperative groups. Pediatr Blood Cancer. 2013;60:1826–32. doi:10.1002/pbc.24683. Jaber OI, Kirby PA. Alveolar Soft Part Sarcoma. Arch Pathol Lab Med. 2015;139:1459–62. doi:10.5858/arpa.2014-0385-RS. Lim JX, Karlsson B, Pang A, Vellayappan BA, Nga V. Stereotactic radiosurgery in alveolar soft part sarcoma brain metastases: Case series and literature review. J Clin Neurosci. 2021;93:227–30. doi:10.1016/j.jocn.2021.09.002. İşleyen ZS, Ay S, Bayram E, Seçmeler Ş, Selvi O, Kılıçkap S, et al. Treatment outcomes of sunitinib and/or pazopanib in advanced alveolar soft part sarcoma: A Turkish Oncology Group (TOG) study. Sci Rep. 2025;15:44124. doi:10.1038/s41598-025-29276-9. Hindi N, Razak A, Rosenbaum E, Jonczak E, Hamacher R, Rutkowski P, et al. Efficacy of immune checkpoint inhibitors in alveolar soft-part sarcoma: results from a retrospective worldwide registry. ESMO Open. 2023;8:102045. doi:10.1016/j.esmoop.2023.102045. Atkins MB, Plimack ER, Puzanov I, Fishman MN, McDermott DF, Cho DC, et al. Axitinib in combination with pembrolizumab in patients with advanced renal cell cancer: a non-randomised, open-label, dose-finding, and dose-expansion phase 1b trial. Lancet Oncol. 2018;19:405–15. doi:10.1016/S1470-2045(18)30081-0. Wilky BA, Trucco MM, Subhawong TK, Florou V, Park W, Kwon D, et al. Axitinib plus pembrolizumab in patients with advanced sarcomas including alveolar soft-part sarcoma: a single-centre, single-arm, phase 2 trial. Lancet Oncol. 2019;20:837–48. doi:10.1016/S1470-2045(19)30153-6. Yuan X, Zhou B, Zhong J. Prognostic factors of alveolar soft part sarcoma in children and adolescents: A population-based study. J Stomatol Oral Maxillofac Surg. 2024;125:101852. doi:10.1016/j.jormas.2024.101852. Tables Tables 1 to 4 are available in the supplementary files section Additional Declarations No competing interests reported. Supplementary Files SupplementaryTable1.xlsx Supplementary Table 1. Clinical and laboratory data for all patients SupplementaryTable2.xlsx Supplementary Table 2. Summary of immunohistochemical staining results for the 20 cases. SupplementaryTable3.xlsx Supplementary Table 3.Summary of radiological characteristics of the 20 cases. Table1.xls Table 1. Summary of patient demographics, preoperative status, and surgical details of the study cohort Table2.xls Table 2. Univariate Analysis of Radiographic Prognostic Factors for Overall Survival in Patients with Alveolar Soft Part Sarcoma. Table3.xls Table 3. Univariate Analysis of Prognostic Factors for Overall Survival in Patients with Alveolar Soft Part Sarcoma. Table4.xls Table 4. Multivariate Analysis of Prognostic Factors for Overall Survival in Alveolar Soft Part Sarcoma. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers invited by journal 06 May, 2026 Editor assigned by journal 02 May, 2026 Submission checks completed at journal 27 Apr, 2026 First submitted to journal 23 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9504084","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":638374129,"identity":"978e7415-367d-4146-b59b-3c5589f8744a","order_by":0,"name":"jian sun","email":"","orcid":"","institution":"University of Shanghai for Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"jian","middleName":"","lastName":"sun","suffix":""},{"id":638374130,"identity":"8165d3f7-92b5-4a46-98fd-731f61b6a169","order_by":1,"name":"Chenglong Zhao","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Chenglong","middleName":"","lastName":"Zhao","suffix":""},{"id":638374131,"identity":"1d3aeaab-86c4-4cfb-ad3c-bde5e99b5e45","order_by":2,"name":"Na Cui","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Na","middleName":"","lastName":"Cui","suffix":""},{"id":638374132,"identity":"12ccfbe5-26c1-47c9-8a51-166035625cba","order_by":3,"name":"Zhenhua Zhou","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Zhenhua","middleName":"","lastName":"Zhou","suffix":""},{"id":638374133,"identity":"4eea9ebd-61eb-4709-a8b5-341914125da3","order_by":4,"name":"Haiyi Gong","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Haiyi","middleName":"","lastName":"Gong","suffix":""},{"id":638374134,"identity":"03cf5e0e-7e94-43c1-bdda-d3ca5d4bd72e","order_by":5,"name":"Haocheng Zhu","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Haocheng","middleName":"","lastName":"Zhu","suffix":""},{"id":638374135,"identity":"97de5bb8-8ffb-41f4-a570-c9c282bd8c82","order_by":6,"name":"Zhipeng Wu","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Zhipeng","middleName":"","lastName":"Wu","suffix":""},{"id":638374136,"identity":"843fd77e-37b0-495d-82c4-df499292ded2","order_by":7,"name":"Ting Wang","email":"","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":false,"prefix":"","firstName":"Ting","middleName":"","lastName":"Wang","suffix":""},{"id":638374137,"identity":"a99f4999-88cf-4546-bcd8-4ea093ad0b25","order_by":8,"name":"Jianru Xiao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2UlEQVRIiWNgGAWjYBACxmYIzcPAwHz4wQcDGztStLClGc4oSEsmxUIeA2meD4cYGwipY25nfva4su2wDH97W4KxjcEBZgb2w0c34HcYm7nh2bY0Hokzhw88zjG4w8fAk5Z2A78WBjPJxjYbHoYbaQnGOQbPmBkkeMwIaGH/BtQiwSN/I8dA2sLgMGMDYS08EFsMQFoYiNRSJtlwLo3H8MyxNMMeg7RkNkJ+Mew/vk2yoeywvdzx5sMPfvyxseNnP3wMv5YGdBE2fMpBQJ6QglEwCkbBKBgFDABEBEYDC4prbgAAAABJRU5ErkJggg==","orcid":"","institution":"Shanghai Changzheng Hospital","correspondingAuthor":true,"prefix":"","firstName":"Jianru","middleName":"","lastName":"Xiao","suffix":""}],"badges":[],"createdAt":"2026-04-23 08:24:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9504084/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9504084/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":109303824,"identity":"2a590a3e-8912-4137-a4b4-d704522de8e6","added_by":"auto","created_at":"2026-05-15 09:40:55","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":566963,"visible":true,"origin":"","legend":"\u003cp\u003ePatient flow diagram\u003c/p\u003e","description":"","filename":"Fig1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/ad40886edc0284c667cd30fe.jpg"},{"id":109303889,"identity":"c5fecc76-8b71-4ad2-ae45-5e72776161dc","added_by":"auto","created_at":"2026-05-15 09:41:00","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":389451,"visible":true,"origin":"","legend":"\u003cp\u003eClinical imaging and intraoperative records of a patient (Case 16) with alveolar soft part sarcoma. (A-B) Preoperative anteroposterior and lateral lumbosacral radiographs show pre-existing spinal instrumentation and subtle density alteration in the L5 vertebral body. (C-D) Axial and sagittal CT reconstruction images demonstrate aggressive osteolytic destruction of the vertebral structure. (E) T1-weighted MRI sequence reveals a homogeneously iso-intense tumor signal. (F) The corresponding T2-weighted imaging shows a lesion with iso-intense signal characteristics. (G-H) Post-contrast MR images display a heterogeneous enhancement pattern within the tumor tissue. (I-J) Intraoperative photographs document spinal reconstruction achieved with posterior vertebral body prosthesis following En-bloc spondylectomy. (K-L) Postoperative radiographs confirm appropriate positioning of the instrumentation and restoration of satisfactory spinal alignment. Abbreviations: CT = computed tomography; MRI = magnetic resonance imaging.\u003c/p\u003e","description":"","filename":"Fig2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/28d1207af03bbab464a27073.jpg"},{"id":109303881,"identity":"85aeaf7e-ddf9-49ea-9f4e-0454ae5a91b7","added_by":"auto","created_at":"2026-05-15 09:41:00","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":3521317,"visible":true,"origin":"","legend":"\u003cp\u003eThe H\u0026amp;E staining (A-B) and IHC staining results for Ki-67 (C) and TFE3 (D) in an alveolar soft part sarcoma patient (Case 15).\u003c/p\u003e","description":"","filename":"Fig3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/f802a0f0a0148c85b9053187.jpg"},{"id":109303819,"identity":"636c958d-2288-4192-af90-4aa4a6d99ea0","added_by":"auto","created_at":"2026-05-15 09:40:54","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":172914,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan-Meier curves for overall survival (OS) based on independent prognostic factors in patients with alveolar soft part sarcoma. (A) Frankel grade. (B) Immunotherapy. (C) Surgical approach.\u003c/p\u003e","description":"","filename":"Fig4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/f53cbd564dc1de0246279422.jpg"},{"id":109405536,"identity":"bd6fd94e-03fb-4548-9707-6f6abae52589","added_by":"auto","created_at":"2026-05-17 13:18:50","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":16972,"visible":true,"origin":"","legend":"\u003cp\u003eSupplementary Table 1. Clinical and laboratory data for all patients\u003c/p\u003e","description":"","filename":"SupplementaryTable1.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/8643b2438406f17d7fa25b8a.xlsx"},{"id":109303882,"identity":"42c23ae8-20f2-451f-bc60-839fa42a2d8b","added_by":"auto","created_at":"2026-05-15 09:41:00","extension":"xlsx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":11492,"visible":true,"origin":"","legend":"\u003cp\u003eSupplementary Table 2. Summary of immunohistochemical staining results for the 20 cases.\u003c/p\u003e","description":"","filename":"SupplementaryTable2.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/9c287a72805bd86c8442bde1.xlsx"},{"id":109303825,"identity":"5326dee9-863b-402c-a110-fd8f63acbe1d","added_by":"auto","created_at":"2026-05-15 09:40:55","extension":"xlsx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":12030,"visible":true,"origin":"","legend":"\u003cp\u003eSupplementary Table 3.Summary of radiological characteristics of the 20 cases.\u003c/p\u003e","description":"","filename":"SupplementaryTable3.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/78bf34aad95bb3c0ec1efef2.xlsx"},{"id":109303836,"identity":"de33a0b1-64d4-42f6-b8eb-5451826de1ca","added_by":"auto","created_at":"2026-05-15 09:40:58","extension":"xls","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":37376,"visible":true,"origin":"","legend":"\u003cp\u003eTable 1. Summary of patient demographics, preoperative status, and surgical details of the study cohort\u003c/p\u003e","description":"","filename":"Table1.xls","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/d2d54df6bb84fed2757934a3.xls"},{"id":109303888,"identity":"eea7dca9-0ca0-41b2-9d05-d2c5c4110795","added_by":"auto","created_at":"2026-05-15 09:41:00","extension":"xls","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":33792,"visible":true,"origin":"","legend":"\u003cp\u003eTable 2. Univariate Analysis of Radiographic Prognostic Factors for Overall Survival in Patients with Alveolar Soft Part Sarcoma.\u003c/p\u003e","description":"","filename":"Table2.xls","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/e66c8b3f4618f3afee3c7f12.xls"},{"id":109303768,"identity":"8741f48b-9544-4a18-81a5-17be1d588025","added_by":"auto","created_at":"2026-05-15 09:40:49","extension":"xls","order_by":6,"title":"","display":"","copyAsset":false,"role":"supplement","size":41984,"visible":true,"origin":"","legend":"\u003cp\u003eTable 3. Univariate Analysis of Prognostic Factors for Overall Survival in Patients with Alveolar Soft Part Sarcoma.\u003c/p\u003e","description":"","filename":"Table3.xls","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/9ba6be1e63ed33406e7aa39e.xls"},{"id":109303826,"identity":"68be3e13-be74-4005-9d22-96068446e5d4","added_by":"auto","created_at":"2026-05-15 09:40:55","extension":"xls","order_by":7,"title":"","display":"","copyAsset":false,"role":"supplement","size":28160,"visible":true,"origin":"","legend":"\u003cp\u003eTable 4. Multivariate Analysis of Prognostic Factors for Overall Survival in Alveolar Soft Part Sarcoma.\u003c/p\u003e","description":"","filename":"Table4.xls","url":"https://assets-eu.researchsquare.com/files/rs-9504084/v1/824be76fd392fd47b58eb0ee.xls"}],"financialInterests":"No competing interests reported.","formattedTitle":"Clinical Characteristics, Radiological Findings, Treatment Patterns, and Prognostic Factors in Spinal Alveolar Soft Part Sarcoma: A Retrospective Study of 20 Patients","fulltext":[{"header":"Background","content":"\u003cp\u003eAlveolar soft part sarcoma (ASPS) is a rare malignancy of uncertain origin that accounts for approximately 1% of soft tissue sarcomas and is classified as an ultra-rare sarcoma[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. First described by Christopherson et al. in 1952[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], ASPS predominantly affects young adults aged 15 to 35 years, with a higher incidence in females before age 30 and in males thereafter[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Common primary sites include the lower extremities, trunk, and head and neck[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Rare primary sites have also been reported in the intestine, lung, uterus, intracranial region, tongue, and spleen[\u003cspan additionalcitationids=\"CR6 CR7 CR8 CR9\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. According to the BSTTR database, approximately 72% of patients present with metastases, most commonly involving the lung, bone, brain, and liver[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSurgical resection remains the primary curative treatment modality[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Spinal ASPS is exceptionally rare and is often accompanied by marked neurological impairment, leading some authors to advocate aggressive surgical intervention[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. However, spinal surgery carries substantial risk. The tumor's rich vascularity and locally destructive behavior complicate resection[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], and radical en-bloc excision is especially challenging because of the risk of massive hemorrhage and injury to critical neurovascular structures.\u003c/p\u003e \u003cp\u003eAt the molecular level, ASPS is characterized by the ASPSCR1::TFE3 fusion gene, which drives tumorigenesis and angiogenesis[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Radiologically, ASPS is typically hypervascular[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] and often demonstrates intratumoral flow-void signs[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e], which helps explain its propensity for severe intraoperative bleeding. ASPS is generally insensitive to conventional chemotherapy[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], and the role of adjuvant radiotherapy remains controversial[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. More recently, targeted therapy and immunotherapy have shown promise. VEGF-targeting tyrosine kinase inhibitors (TKIs) are biologically rational because of the angiogenic nature of ASPS[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], while the highly vascular tumor microenvironment may also facilitate immune infiltration and antigen presentation[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Atezolizumab monotherapy has achieved an objective response rate (ORR) of 37%[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], and PD-L1 blockade combined with TKIs has produced ORRs exceeding 80% with median progression-free survival (PFS) longer than 35 months[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Nonetheless, these data remain limited, and the prognosis of metastatic ASPS is still poor[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe rarity of spinal ASPS means that robust evidence on optimal surgery, perioperative care, adjuvant therapy, and prognostic factors is still lacking. We retrospectively analyzed 20 patients with spinal ASPS treated at our institution between January 1, 2012 and December 31, 2023. This study aimed to characterize their clinical features, surgical and perioperative characteristics, and radiological manifestations, to evaluate treatment efficacy, and to identify independent prognostic factors that may help guide clinical decision-making.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients\u003c/h2\u003e \u003cp\u003eData were collected from patients with alveolar soft part sarcoma who underwent surgical treatment in the Department of Orthopedic Oncology at our institution between January 1, 2012 and December 31, 2023. All patients had a postoperative pathological diagnosis of ASPS. Inclusion criteria were as follows: (1) resection of a spinal lesion in our department; and (2) postoperative pathological confirmation of ASPS. Exclusion criteria were: (1) ASPS lesions located outside the spine (n\u0026thinsp;=\u0026thinsp;9); (2) biopsy suggesting ASPS without subsequent surgical resection (n\u0026thinsp;=\u0026thinsp;4); and (3) loss to follow-up (n\u0026thinsp;=\u0026thinsp;2) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The final cohort included 20 patients: 3 cervical, 7 thoracic, 7 lumbar, and 3 sacral cases.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e This retrospective cohort study was approved by the Medical Ethics Committee of Shanghai Changzheng Hospital (Approval No. 2018SL004). Written informed consent to participate was obtained from all patients or their legal guardians.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePatient Characteristics\u003c/h3\u003e\n\u003cp\u003ePatient-related variables included sex, age, smoking history, symptoms, preoperative metastasis, Frankel grade, and Karnofsky Performance Status (KPS) score. Tumor-related variables included location, number of involved segments, tumor diameter, Ki-67 index, preoperative Epidural Spinal Cord Compression (ESCC) score, and Spinal Instability Neoplastic Score (SINS). Laboratory variables included preoperative erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), D-dimer, hemoglobin (Hb), albumin (ALB), and postoperative day 1 hemoglobin (POD1 Hb). Treatment-related variables included preoperative embolization, surgical strategy, adjuvant immunotherapy, and postoperative radiotherapy. Clinical records, surgical details, imaging examinations, and pathological findings were retrieved from the institutional database and hospital records. Overall survival events were calculated from the date of surgery to death or last follow-up through July 1, 2024. Patients were followed in the outpatient clinic at 3, 6, and 12 months postoperatively, every 6 months during the second postoperative year, and annually thereafter. Because many patients already had metastases before surgery, progression-free survival was difficult to assess reliably.\u003c/p\u003e\n\u003ch3\u003eRadiological Analysis\u003c/h3\u003e\n\u003cp\u003eRadiological data from CT and MRI were retrieved from patient archives. Imaging characteristics were evaluated by radiologists and included tumor location, size, boundaries, distant metastases, internal and peripheral structure, density/signal intensity, intratumoral flow voids, enhancement pattern, and extent of bone destruction. T1WI and T2WI signal intensity were interpreted relative to adjacent muscle signal on the corresponding sequence.\u003c/p\u003e\n\u003ch3\u003eStatistical Methods\u003c/h3\u003e\n\u003cp\u003eData were analyzed using SPSS Statistics version 22.0 (IBM, New York, USA) and GraphPad Prism version 8.0.2 (GraphPad Software, California, USA). Categorical variables were compared using the chi-square test or Fisher\u0026rsquo;s exact test (two-tailed), as appropriate. Continuous variables were compared using parametric methods as appropriate. Overall survival (OS) was defined as the primary endpoint and was analyzed using the Kaplan\u0026ndash;Meier method. Differences were assessed with the log-rank test. Variables with P\u0026thinsp;\u0026lt;\u0026thinsp;0.1 on univariate analysis were entered into multivariate Cox regression using a backward selection method. A two-sided P value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eClinical Characteristics, Surgical Interventions, and Prognostic Outcomes\u003c/h2\u003e \u003cp\u003eA total of 20 patients who underwent surgery for spinal ASPS lesions were included in this study, comprising 17 males and 3 females, with a mean age of 33.95 years (range, 16\u0026ndash;63 years). Fourteen patients (70.0%) had metastatic disease, including 12 with metastases before surgery and 2 who developed metastases after surgery. The most common metastatic sites were the skeletal system (including the spine, skull, and ribs; 12/14, 85.71%) and the lungs (10/14, 71.43%); one patient each had liver and brain metastases. Most patients presented with overlapping symptoms before surgery. Pain was the most common symptom and was documented in 10 patients, mainly involving the lumbosacral region, buttock, and upper or lower extremities. Motor dysfunction was present in 11 patients, including 9 with lower-extremity motor impairment: 4 with complete paraplegia, 3 with bilateral lower-extremity weakness, and 2 with unilateral lower-extremity paralysis or weakness. Some patients also had incomplete paresis of the upper extremities. Sensory disturbance or numbness was present in 4 patients, all involving the left upper and/or lower extremities. In 2 patients, the lesion was detected incidentally during physical examination. The main surgical indications in this cohort were neurological dysfunction caused by compression, intractable pain, increasing local tumor burden, and reconstruction of instability caused by osseous destruction (Table\u0026nbsp;1).\u003c/p\u003e \u003cp\u003eAll patients underwent posterior tumor resection and reconstruction. Among the 12 patients who underwent en-bloc resection, reconstruction was performed using pedicle screws plus titanium mesh in 9 cases and pedicle screws plus an artificial vertebral body in 3 cases. Among the 8 patients who underwent subtotal resection, reconstruction consisted of pedicle screws alone in 3 cases, pedicle screws plus titanium mesh in 2 cases, pedicle screws plus bone cement in 2 cases, and cement-augmented screws in 1 case. Seven patients underwent selective preoperative arterial embolization.\u003c/p\u003e \u003cp\u003eThe perioperative hematologic burden was substantial. Mean intraoperative blood loss for the entire cohort was 2400 mL (median, 1900 mL; range, 400\u0026ndash;7000 mL). Stratified by surgical approach, the mean blood loss was 1950 mL in the en-bloc group and 3075 mL in the subtotal resection group. Sixteen patients required intraoperative transfusion; among these 16 patients, the mean transfusion volume was 2225 mL (median, 1700 mL; range, 400\u0026ndash;5200 mL). Mean preoperative hemoglobin was 135.8 g/L and decreased to 102.5 g/L on postoperative day 1, corresponding to an average decline of approximately 33.4 g/L.\u003c/p\u003e \u003cp\u003eEarly postoperative clinical outcomes showed that 11 patients (55.0%) achieved significant symptom relief or neurological improvement, 4 patients (20.0%) experienced partial improvement (for example, pain or sensory improvement without definite motor recovery), 4 patients (20.0%) remained stable or showed only limited improvement, and 1 patient (5.0%) developed definite postoperative neurological deterioration. Three patients experienced documented perioperative complications: one had bilateral lower-extremity edema, severe systemic infection, and pleural effusion; one developed isolated pleural effusion; and one experienced dural injury with cerebrospinal fluid leakage. No patient died from perioperative complications. Postoperative adjuvant treatment included radiotherapy in 11 patients, immunotherapy in 8 patients, and targeted therapy in 7 patients. Postoperative pathology confirmed ASPS in all cases (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Immunohistochemical analysis of the surgical specimens (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) showed that TFE3 nuclear positivity was the most frequent finding, present in 94.12% of tested cases (16/17), supporting its role as a key diagnostic marker. Other markers included Vimentin (66.67%, 10/15), PAS (90.00%, 9/10), MyoD1 (47.37%, 9/19), NSE (60.00%, 6/10), EMA (28.57%, 4/14), CK (pan) (15.79%, 3/19), S100 (16.67%, 3/18), and Desmin (18.75%, 3/16) (Supplementary Table\u0026nbsp;2). During a mean follow-up of 33.15 months (maximum, 120 months), 9 patients were alive and 11 had died by the last follow-up.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eRadiological Manifestations and Prognosis\u003c/h3\u003e\n\u003cp\u003eAmong the 20 patients, 18 underwent MRI and 16 underwent CT of the spinal lesion planned for surgery. On MRI, 10 cases (55.56%) showed heterogeneous enhancement and 8 cases (44.44%) showed uniform enhancement. On T1-weighted images, 13 cases (72.22%) were hypointense and 5 cases (27.78%) were isointense. On T2-weighted images, 9 cases (50.00%) were hyperintense and 9 cases (50.00%) were isointense. Tumor boundaries were clear in 8 cases (44.4%) and unclear in 10 cases (55.6%). Flow voids were identified in 16 cases (88.89%). On CT, 12 of 16 cases (75.00%) showed osteolytic bone destruction and 4 of 16 cases (25.00%) showed osteoblastic destruction. All 16 lesions examined with contrast-enhanced CT showed definite enhancement (Supplementary Table\u0026nbsp;3).\u003c/p\u003e \u003cp\u003eUnivariate analysis of preoperative radiological factors (Table\u0026nbsp;2) showed that tumor boundary (clear vs blurred, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), MRI enhancement pattern (uniform vs heterogeneous, P\u0026thinsp;=\u0026thinsp;0.013), and T2WI signal intensity (isointense vs hyperintense, P\u0026thinsp;=\u0026thinsp;0.032) were significantly associated with prognosis. T1WI signal intensity (P\u0026thinsp;=\u0026thinsp;0.297), flow voids (P\u0026thinsp;=\u0026thinsp;0.139), and CT bone destruction pattern (P\u0026thinsp;=\u0026thinsp;0.280) were not statistically significant.\u003c/p\u003e\n\u003ch3\u003eClinicopathological Features and Survival Analysis\u003c/h3\u003e\n\u003cp\u003eThe 1-year OS rate after surgery for spinal ASPS was 70.0%, and the median OS was 28.0 months (95% CI, 7.6\u0026ndash;48.4). We further evaluated the impact of clinicopathological variables on survival using univariate (Table\u0026nbsp;3) and multivariate (Table\u0026nbsp;4) analyses. Univariate analysis showed that elevated D-dimer (\u0026gt;\u0026thinsp;1 mg/L; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), elevated CRP (\u0026gt;\u0026thinsp;10 mg/L; P\u0026thinsp;=\u0026thinsp;0.001), and hypoalbuminemia (ALB\u0026thinsp;\u0026lt;\u0026thinsp;40 g/L; P\u0026thinsp;=\u0026thinsp;0.009) were associated with poorer prognosis. Functional status indicators were also important: preoperative neurological deficit (Frankel grade A\u0026ndash;C; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and poorer performance status (KPS\u0026thinsp;\u0026lt;\u0026thinsp;80; P\u0026thinsp;=\u0026thinsp;0.015) were associated with shorter survival. Spinal instability (SINS\u0026thinsp;\u0026ge;\u0026thinsp;7; P\u0026thinsp;=\u0026thinsp;0.010) and elevated ESR (\u0026gt;\u0026thinsp;10 mm/h; P\u0026thinsp;=\u0026thinsp;0.015) were also adverse prognostic factors. At the treatment level, receiving immunotherapy (P\u0026thinsp;=\u0026thinsp;0.007) and undergoing en-bloc resection (P\u0026thinsp;=\u0026thinsp;0.045) were associated with longer survival. In contrast, age, sex, tumor size, number of involved segments, and Ki-67 index were not significantly associated with prognosis in this cohort.\u003c/p\u003e \u003cp\u003eMultivariate Cox regression identified three variables of interest: postoperative immunotherapy (HR\u0026thinsp;=\u0026thinsp;0.092, 95% CI 0.010\u0026ndash;0.888; P\u0026thinsp;=\u0026thinsp;0.039), preoperative Frankel grade D\u0026ndash;E (HR\u0026thinsp;=\u0026thinsp;0.079, 95% CI 0.013\u0026ndash;0.490; P\u0026thinsp;=\u0026thinsp;0.006), and en-bloc resection (HR\u0026thinsp;=\u0026thinsp;0.236, 95% CI 0.049\u0026ndash;1.127; P\u0026thinsp;=\u0026thinsp;0.070) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Immunotherapy and better preoperative neurological status were independent protective factors, whereas en-bloc resection showed a favorable trend that did not reach conventional statistical significance.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eASPS is a rare mesenchymal neoplasm accounting for less than 1% of all sarcomas, with an estimated annual incidence of 1.2 per 10\u0026nbsp;million population[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Its defining genomic alteration is the t(X;17)(p11;q25) translocation, which fuses ASPSCR1 and TFE3 to generate the oncogenic ASPSCR1::TFE3 fusion protein[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. In diagnostic practice, TFE3 immunohistochemistry has high sensitivity, generally exceeding 95%[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], which is consistent with the 94.12% positivity rate (16/17) observed in our cohort. TFE3 expression is also useful in differentiating ASPS from entities such as paraganglioma and granular cell tumor[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], and it has been recognized as a key diagnostic marker in multiple clinicopathologic studies[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe ASPSCR1::TFE3-driven angiogenic program renders ASPS highly hypervascular[\u003cspan additionalcitationids=\"CR31\" citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Although hypervascularity is not specific and can also be seen in other spinal sarcomas, its presence has important operational implications[\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. In our series, spinal ASPS most commonly appeared hypointense or slightly hypointense on T1-weighted imaging (72.22%), differing somewhat from previous reports of extremity ASPS, which more often appears isointense or slightly hyperintense[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. ASPS is typically described as intermediate to high signal on T2-weighted imaging[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]; in our cohort, patients with isointense T2WI signals had better survival than those with hyperintense signals (P\u0026thinsp;=\u0026thinsp;0.032). All tumors enhanced after contrast administration, and uniform enhancement (P\u0026thinsp;=\u0026thinsp;0.013) as well as a clear tumor boundary (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) were associated with a more favorable prognosis. These findings suggest that preoperative imaging may help estimate biological behavior and risk.\u003c/p\u003e \u003cp\u003eIntraoperative blood loss in spinal ASPS was considerable, averaging 2400 mL and reaching 7000 mL in the most extreme case, which is markedly higher than the average blood loss reported for general oncologic spine surgery (approximately 1176\u0026thinsp;\u0026plusmn;\u0026thinsp;1209 mL)[\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. In our cohort, 80.0% of patients required perioperative transfusion, with a mean transfusion volume of 2225 mL, and mean hemoglobin fell by more than 30 g/L on postoperative day 1. Although only 35.0% of patients underwent selective preoperative embolization, these findings strongly support routine preoperative pathologic confirmation, consideration of selective embolization, adequate blood preparation, and meticulous intraoperative hemostatic planning for spinal ASPS with imaging features suggestive of hypervascularity.\u003c/p\u003e \u003cp\u003eFor spinal ASPS, surgery is the mainstay of local control, but its risks and benefits must be weighed carefully. For soft tissue ASPS, complete resection is generally preferred whenever feasible[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. However, because spinal ASPS is extremely uncommon, surgical indications are not well defined. Spinal surgery itself carries substantial risks, including neurologic injury, uncontrollable hemorrhage, and postoperative complications[\u003cspan additionalcitationids=\"CR37\" citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Current surgical principles for primary spinal sarcomas generally favor aggressive resection, particularly en bloc resection when feasible and oncologically appropriate[\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. For metastatic spinal disease, surgery is usually guided by expected survival: palliative surgery may be considered when life expectancy is at least 3 months[\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e], whereas en-bloc resection is generally reserved for selected patients with an anticipated survival of 12\u0026ndash;24 months[\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eOur data suggest that patients treated with en-bloc resection tended to have better survival than those treated with piecemeal subtotal resection. In multivariate analysis, en-bloc resection showed a trend toward prolonged survival (HR\u0026thinsp;=\u0026thinsp;0.236, 95% CI 0.049\u0026ndash;1.127; P\u0026thinsp;=\u0026thinsp;0.070), although statistical significance was not reached, likely because of the limited sample size. Importantly, this finding should be interpreted in the context of patient selection. In our cohort, the main drivers for surgery were neurologic compromise, intractable pain, local tumor burden, and the need to reconstruct spinal stability. Patients selected for en-bloc resection generally had more favorable tumor boundaries, better resectability, and better overall physiologic reserve. Therefore, the apparent survival advantage should not be attributed solely to the surgical technique itself, but rather interpreted within the broader framework of case selection and surgical feasibility.\u003c/p\u003e \u003cp\u003eFor advanced soft tissue sarcoma, systemic treatment has traditionally relied on cytotoxic chemotherapy[\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e], but chemotherapy is generally ineffective in ASPS[\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. ASPS is also often considered relatively radioresistant[\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e], and the value of radiotherapy remains debated[\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e]. Nevertheless, some authors support high-dose radiotherapy for selected settings such as brain metastases[\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e]. In our cohort, 11 patients received postoperative radiotherapy. Although radiotherapy was not associated with improved OS in this cohort, it may still have a role in selected patients, particularly for local control when recurrence would be clinically devastating.\u003c/p\u003e \u003cp\u003eRecent studies have shown activity with tyrosine kinase inhibitors and immune checkpoint inhibitors in advanced ASPS. TKIs such as sunitinib and pazopanib have shown meaningful disease control in advanced ASPS[\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e], and ASPS is considered one of the sarcoma subtypes most likely to benefit from immune checkpoint inhibition[\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e]. Atezolizumab has induced durable responses in approximately one-third of patients with advanced ASPS[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. VEGF signaling may also contribute to immune evasion[\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e], providing a rationale for combined anti-angiogenic and PD-1/PD-L1 blockade. In a phase II study of axitinib plus pembrolizumab in advanced sarcoma, 6 of 11 patients with ASPS achieved partial response and 2 achieved stable disease[\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e]. In our study, multivariate analysis identified postoperative immunotherapy as an independent protective factor for OS, supporting its role as an important component of postoperative systemic management. Although targeted therapy was not significantly associated with improved OS in this cohort, immunotherapy combined with targeted therapy remains a rational option for patients with unresectable disease or suboptimal surgical margins.\u003c/p\u003e \u003cp\u003eWith respect to prognostic markers, prior studies have focused mainly on tumor burden, primary site, metastatic status, and treatment modality[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e]. Our data also highlight the importance of host status and inflammatory biomarkers. Elevated D-dimer and C-reactive protein, which may reflect hypercoagulability and systemic inflammation, and hypoalbuminemia, which may reflect poor nutritional reserve, were all associated with worse survival. These findings suggest that prognosis in spinal ASPS is influenced not only by tumor-related variables but also by systemic host condition. Together with the protective associations observed for immunotherapy and better preoperative neurologic status, these results support the view that prognosis in spinal ASPS is multidimensional rather than determined by a single factor.\u003c/p\u003e \u003cp\u003eThis study has several limitations. First, the sample size was small, with only 20 patients, which limits statistical power. Second, radiological data were incomplete for some patients, and diffusion-weighted imaging was not available, limiting comprehensive radiologic assessment. Third, because of the retrospective design, targeted therapy and immunotherapy were not standardized, and different drugs were used across patients. Larger prospective studies are needed to confirm these findings. Nonetheless, this study provides preliminary evidence supporting the clinical relevance of imaging features, surgical strategy, and immunotherapy in spinal ASPS.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eSpinal ASPS is a rare, highly vascular malignancy that presents major surgical and oncological challenges. In this cohort, postoperative immunotherapy and better preoperative neurological status were independently associated with improved survival, while en-bloc resection showed a favorable but non-significant survival trend. Careful preoperative evaluation, including tissue diagnosis and consideration of selective embolization, may help optimize surgical planning. When technically feasible and compatible with neurological preservation, en-bloc resection remains a reasonable surgical goal. Given the rarity of the disease and the limitations of retrospective single-center data, larger multicenter studies are required to clarify the roles of surgery, radiotherapy, targeted therapy, and immunotherapy in the management of spinal ASPS.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eASPS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eAlveolar soft part sarcoma\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eALB\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eAlbumin\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCRP\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eC-reactive protein\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eCT\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eComputed tomography\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eESCC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eEpidural Spinal Cord Compression\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eESR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eErythrocyte sedimentation rate\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eHb\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eHemoglobin\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eKPS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eKarnofsky Performance Status\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMRI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMagnetic resonance imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eORR\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eObjective response rate\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eOS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eOverall survival\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePAS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePeriodic acid\u0026ndash;Schiff\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePFS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eProgression-free survival\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePOD1 Hb\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePostoperative day 1 hemoglobin\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSINS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSpinal Instability Neoplastic Score\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eTKI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eTyrosine kinase inhibitor\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eT1WI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eT1-weighted imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eT2WI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eT2-weighted imaging\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research project was examined and approved by the Medical Ethics Committee of Shanghai Changzheng Hospital (Approval No. 2018SL004), and written informed consent was obtained from all patients or their legal guardians.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from all patients for the publication of this study and any accompanying images.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data generated or analysed during this study are included in this published article and its supplementary information files.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by the National Natural Science Foundation of China (Grant Nos. 82372910 and 82273471), the Shanghai Orthopedic Research Center for Spinal Disorders and Traumatology (Grant No. 21MC1930100), and the Shanghai Municipal Science and Technology Commission Orthopedic Clinical Medical Research Center Construction Project (Grant No. 20222Z01013). The funding bodies had no role in the design of the study, data collection, analysis, interpretation of data, or writing of the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eZ.W., T.W., and J.X. contributed to the study conception and design. Material preparation and data collection were performed by N.C. and J.S. Statistical analysis was performed by J.S. T.W., C.Z., Z.Z., H.G., H.Z., Z.W., and J.X. were responsible for the treatment of patients. The first draft of the manuscript was written by T.W. and J.S. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJ.S., C.Z., and N.C. contributed equally to this work and should be considered co-first authors.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBrahmi M, Vanacker H, Dufresne A. Novel therapeutic options for alveolar soft part sarcoma: antiangiogenic therapy, immunotherapy and beyond. Curr Opin Oncol. 2020;32:295\u0026ndash;300. doi:10.1097/CCO.0000000000000652.\u003c/li\u003e\n\u003cli\u003eChristopherson WM, Foote FW, Stewart FW. Alveolar soft-part sarcomas; structurally characteristic tumors of uncertain histogenesis. Cancer. 1952;5:100\u0026ndash;11. doi:10.1002/1097-0142(195201)5:1%3C100::aid-cncr2820050112%3E3.0.co;2-k.\u003c/li\u003e\n\u003cli\u003ePaoluzzi L, Maki RG. Diagnosis, Prognosis, and Treatment of Alveolar Soft-Part Sarcoma: A Review. JAMA Oncol. 2019;5:254. doi:10.1001/jamaoncol.2018.4490.\u003c/li\u003e\n\u003cli\u003eFujiwara T, Kunisada T, Nakata E, Nishida K, Yanai H, Nakamura T, et al. Advances in treatment of alveolar soft part sarcoma: an updated review. Jpn J Clin Oncol. 2023;53:1009\u0026ndash;18. doi:10.1093/jjco/hyad102.\u003c/li\u003e\n\u003cli\u003eGong Y, Liu M, Wu Q, Liu Y, Zhang J, Yao L, et al. Alveolar soft part sarcoma of the tongue: a case report and review of the literature. Int J Clin Exp Pathol. 2020;13:1275\u0026ndash;82.\u003c/li\u003e\n\u003cli\u003eZhao J, Peng J, Liu J, Deng Q, Pang X. Primary Alveolar Soft-Part Sarcoma of the Lung: A Case Report. 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Head Neck Pathol. 2023;17:265\u0026ndash;74. doi:10.1007/s12105-022-01505-x.\u003c/li\u003e\n\u003cli\u003eGu\u0026eacute;rin R, Menard A-L, Angot E, Piton N, Vera P, Schwarz L, et al. An unusual case of primary splenic soft part alveolar sarcoma: case report and review of the literature with emphasis on the spectrum of TFE3-associated neoplasms. Diagn Pathol. 2024;19:62. doi:10.1186/s13000-024-01483-4.\u003c/li\u003e\n\u003cli\u003eFujiwara T, Nakata E, Kunisada T, Ozaki T, Kawai A. Alveolar soft part sarcoma: progress toward improvement in survival? A population-based study. BMC Cancer. 2022;22:891. doi:10.1186/s12885-022-09968-5.\u003c/li\u003e\n\u003cli\u003eZhang Y, Huang Y, Qin Y, Yang N, Yang P, Li N, et al. Alveolar soft part sarcoma: a clinicopathological and immunohistochemical analysis of 26 cases emphasizing risk factors and prognosis. Diagn Pathol. 2024;19:23. doi:10.1186/s13000-024-01450-z.\u003c/li\u003e\n\u003cli\u003eHagerty BL, Aversa J, Diggs LP, Dominguez DA, Ayabe RI, Blakely AM, et al. Characterization of alveolar soft part sarcoma using a large national database. Surgery. 2020;168:825\u0026ndash;30. doi:10.1016/j.surg.2020.06.007.\u003c/li\u003e\n\u003cli\u003eLuzzati AD, Shah SP, Gagliano FS, Perrucchini GG, Fontanella W, Alloisio M. Four- and five- level en bloc spondylectomy for malignant spinal tumors. Spine (Phila Pa 1976). 2014;39:E129\u0026ndash;139. doi:10.1097/BRS.0000000000000072.\u003c/li\u003e\n\u003cli\u003eTanaka M, Chuaychob S, Homme M, Yamazaki Y, Lyu R, Yamashita K, et al. ASPSCR1::TFE3 orchestrates the angiogenic program of alveolar soft part sarcoma. Nat Commun. 2023;14:1957. doi:10.1038/s41467-023-37049-z.\u003c/li\u003e\n\u003cli\u003eSood S, Baheti AD, Shinagare AB, Jagannathan JP, Hornick JL, Ramaiya NH, et al. Imaging features of primary and metastatic alveolar soft part sarcoma: single institute experience in 25 patients. Br J Radiol. 2014;87:20130719. doi:10.1259/bjr.20130719.\u003c/li\u003e\n\u003cli\u003eSpinnato P, Papalexis N, Colangeli M, Miceli M, Cromb\u0026eacute; A, Parmeggiani A, et al. Imaging Features of Alveolar Soft Part Sarcoma: Single Institution Experience and Literature Review. Clin Pract. 2023;13:1369\u0026ndash;82. doi:10.3390/clinpract13060123.\u003c/li\u003e\n\u003cli\u003eCui J-F, Chen H-S, Hao D-P, Liu J-H, Hou F, Xu W-J. Magnetic Resonance Features and Characteristic Vascular Pattern of Alveolar Soft-Part Sarcoma. Oncol Res Treat. 2017;40:580\u0026ndash;5. doi:10.1159/000477443.\u003c/li\u003e\n\u003cli\u003eReichardt P, Lindner T, Pink D, Thuss-Patience PC, Kretzschmar A, D\u0026ouml;rken B. Chemotherapy in alveolar soft part sarcomas. What do we know? Eur J Cancer. 2003;39:1511\u0026ndash;6. doi:10.1016/s0959-8049(03)00264-8.\u003c/li\u003e\n\u003cli\u003eYou Y, Guo X, Zhuang R, Zhang C, Wang Z, Shen F, et al. Activity of PD-1 Inhibitor Combined With Anti-Angiogenic Therapy in Advanced Sarcoma: A Single-Center Retrospective Analysis. Front Mol Biosci. 2021;8:747650. doi:10.3389/fmolb.2021.747650.\u003c/li\u003e\n\u003cli\u003eMartin-Broto J, Moura DS, Hindi N. Which sarcoma requires PD1/PDL1 inhibitors, and what should be the best scheme? Present status and next steps. Curr Opin Oncol. 2025;37:331\u0026ndash;8. doi:10.1097/CCO.0000000000001149.\u003c/li\u003e\n\u003cli\u003eChen AP, Sharon E, O\u0026rsquo;Sullivan-Coyne G, Moore N, Foster JC, Hu JS, et al. Atezolizumab for Advanced Alveolar Soft Part Sarcoma. N Engl J Med. 2023;389:911\u0026ndash;21. doi:10.1056/NEJMoa2303383.\u003c/li\u003e\n\u003cli\u003eTan Z, Wu Y, Fan Z, Gao T, Guo W, Bai C, et al. Anlotinib plus TQB2450, a PD-L1 Antibody, in Patients with Advanced Alveolar Soft Part Sarcoma: A Single-Arm, Phase II Trial. Clin Cancer Res. 2024;30:5577\u0026ndash;83. doi:10.1158/1078-0432.CCR-24-2444.\u003c/li\u003e\n\u003cli\u003ede Pinieux G, Karanian M, Le Loarer F, Le Guellec S, Chabaud S, Terrier P, et al. Nationwide incidence of sarcomas and connective tissue tumors of intermediate malignancy over four years using an expert pathology review network. PLoS One. 2021;16:e0246958. doi:10.1371/journal.pone.0246958.\u003c/li\u003e\n\u003cli\u003eLadanyi M, Lui MY, Antonescu CR, Krause-Boehm A, Meindl A, Argani P, et al. The der(17)t(X;17)(p11;q25) of human alveolar soft part sarcoma fuses the TFE3 transcription factor gene to ASPL, a novel gene at 17q25. Oncogene. 2001;20:48\u0026ndash;57. doi:10.1038/sj.onc.1204074.\u003c/li\u003e\n\u003cli\u003eJu X, Sun K, Liu R, Li S, Abulajiang G, Zou H, et al. Exploring the Histogenesis and Diagnostic Strategy Using Immunoassay and RT-PCR in Alveolar Soft Part Sarcoma. Pathol Oncol Res. 2018;24:593\u0026ndash;600. doi:10.1007/s12253-017-0280-9.\u003c/li\u003e\n\u003cli\u003eFolpe AL, Deyrup AT. Alveolar soft-part sarcoma: a review and update. J Clin Pathol. 2006;59:1127\u0026ndash;32. doi:10.1136/jcp.2005.031120.\u003c/li\u003e\n\u003cli\u003eAlbadrani HM, Abduljabbar L. Successful Local Control of Orbital ASPS Using VMAT-Based Adjuvant Radiotherapy with Simultaneous Integrated Boost: A 3-Year Follow-Up Case Report. Int Med Case Rep J. 2025;18:1585\u0026ndash;92. doi:10.2147/IMCRJ.S557971.\u003c/li\u003e\n\u003cli\u003eSoheilifar MH, Taheri RA, Zolfaghari Emameh R, Moshtaghian A, Kooshki H, Motie MR. Molecular Landscape in Alveolar Soft Part Sarcoma: Implications for Molecular Targeted Therapy. Biomed Pharmacother. 2018;103:889\u0026ndash;96. doi:10.1016/j.biopha.2018.04.117.\u003c/li\u003e\n\u003cli\u003eWang S, Wang Y, Xu J, Ren Q, Hu Y, Jia L, et al. Ultrasound characteristics of alveolar soft part sarcoma in pediatric patients: a retrospective analysis. BMC Cancer. 2024;24:1484. doi:10.1186/s12885-024-13262-x.\u003c/li\u003e\n\u003cli\u003eGulati M, Mittal A, Barwad A, Pandey R, Rastogi S, Dhamija E. Imaging and Pathological Features of Alveolar Soft Part Sarcoma: Analysis of 16 Patients. Indian J Radiol Imaging. 2021;31:573\u0026ndash;81. doi:10.1055/s-0041-1735501.\u003c/li\u003e\n\u003cli\u003eMcaddy NC, Saffar H, Liti\u0026egrave;re S, Jespers P, Sch\u0026ouml;ffski P, Messiou C. iCREATE: imaging features of primary and metastatic alveolar soft part sarcoma from the EORTC CREATE study. Cancer Imaging. 2020;20:79. doi:10.1186/s40644-020-00352-9.\u003c/li\u003e\n\u003cli\u003eLedoux P, Kind M, Le Loarer F, Stoeckle E, Italiano A, Tirode F, et al. Abnormal vascularization of soft-tissue sarcomas on conventional MRI: Diagnostic and prognostic values. Eur J Radiol. 2019;117:112\u0026ndash;9. doi:10.1016/j.ejrad.2019.06.007.\u003c/li\u003e\n\u003cli\u003eYuan J, Xie D, Fang S, Meng F, Wu Y, Shan D, et al. Qualitative and quantitative MRI analysis of alveolar soft part sarcoma: correlation with histological grade and Ki-67 expression. Insights Imaging. 2024;15:142. doi:10.1186/s13244-024-01687-8.\u003c/li\u003e\n\u003cli\u003eMohme M, Mende KC, Pantel T, Viezens L, Westphal M, Eicker SO, et al. Intraoperative blood loss in oncological spine surgery. Neurosurg Focus. 2021;50:E14. doi:10.3171/2021.2.FOCUS201117.\u003c/li\u003e\n\u003cli\u003eSwann MC, Hoes KS, Aoun SG, McDonagh DL. Postoperative complications of spine surgery. Best Pract Res Clin Anaesthesiol. 2016;30:103\u0026ndash;20. doi:10.1016/j.bpa.2016.01.002.\u003c/li\u003e\n\u003cli\u003eAnadio JM, Sturm PF, Forslund JM, Agarwal S, Lane A, Tarango C, et al. A bleeding assessment tool correlates with intraoperative blood loss in children and adolescents undergoing major spinal surgery. Thromb Res. 2017;152:82\u0026ndash;6. doi:10.1016/j.thromres.2017.02.020.\u003c/li\u003e\n\u003cli\u003eAndo K, Kobayashi K, Nakashima H, Machino M, Ito S, Kanbara S, et al. Surgical outcomes and factors related to postoperative motor and sensory deficits in resection for 244 cases of spinal schwannoma. J Clin Neurosci. 2020;81:6\u0026ndash;11. doi:10.1016/j.jocn.2020.09.025.\u003c/li\u003e\n\u003cli\u003eYeung CM, Bilsky M, Boland PJ, Vaynrub M. The Role of En Bloc Resection in the Modern Era for Primary Spine Tumors. Spine (Phila Pa 1976). 2024;49:46\u0026ndash;57. doi:10.1097/BRS.0000000000004821.\u003c/li\u003e\n\u003cli\u003eHammerberg KW. Surgical treatment of metastatic spine disease. Spine (Phila Pa 1976). 1992;17:1148\u0026ndash;53. doi:10.1097/00007632-199210000-00004.\u003c/li\u003e\n\u003cli\u003eSundaresan N, Digiacinto GV, Hughes JE, Cafferty M, Vallejo A. Treatment of neoplastic spinal cord compression: results of a prospective study. Neurosurgery. 1991;29:645\u0026ndash;50. doi:10.1097/00006123-199111000-00001.\u003c/li\u003e\n\u003cli\u003eTokuhashi Y, Matsuzaki H, Oda H, Oshima M, Ryu J. A revised scoring system for preoperative evaluation of metastatic spine tumor prognosis. Spine (Phila Pa 1976). 2005;30:2186\u0026ndash;91. doi:10.1097/01.brs.0000180401.06919.a5.\u003c/li\u003e\n\u003cli\u003eKato S, Murakami H, Demura S, Yoshioka K, Yokogawa N, Yonezawa N, et al. Kidney and Thyroid Cancer-Specific Treatment Algorithm for Spinal Metastases: A Validation Study. World Neurosurg. 2019;122:e1305\u0026ndash;11. doi:10.1016/j.wneu.2018.11.040.\u003c/li\u003e\n\u003cli\u003eGamboa AC, Gronchi A, Cardona K. Soft-tissue sarcoma in adults: An update on the current state of histiotype-specific management in an era of personalized medicine. CA Cancer J Clin. 2020;70:200\u0026ndash;29. doi:10.3322/caac.21605.\u003c/li\u003e\n\u003cli\u003eLiu J, Fan Z, Li S, Gao T, Xue R, Bai C, et al. Target therapy for metastatic alveolar soft part sarcoma: a retrospective study with 47 cases. Ann Transl Med. 2020;8:1493. doi:10.21037/atm-20-6377.\u003c/li\u003e\n\u003cli\u003eOrbach D, Brennan B, Casanova M, Bergeron C, Mosseri V, Francotte N, et al. Paediatric and adolescent alveolar soft part sarcoma: A joint series from European cooperative groups. Pediatr Blood Cancer. 2013;60:1826\u0026ndash;32. doi:10.1002/pbc.24683.\u003c/li\u003e\n\u003cli\u003eJaber OI, Kirby PA. Alveolar Soft Part Sarcoma. Arch Pathol Lab Med. 2015;139:1459\u0026ndash;62. doi:10.5858/arpa.2014-0385-RS.\u003c/li\u003e\n\u003cli\u003eLim JX, Karlsson B, Pang A, Vellayappan BA, Nga V. Stereotactic radiosurgery in alveolar soft part sarcoma brain metastases: Case series and literature review. J Clin Neurosci. 2021;93:227\u0026ndash;30. doi:10.1016/j.jocn.2021.09.002.\u003c/li\u003e\n\u003cli\u003eİşleyen ZS, Ay S, Bayram E, Se\u0026ccedil;meler Ş, Selvi O, Kılı\u0026ccedil;kap S, et al. Treatment outcomes of sunitinib and/or pazopanib in advanced alveolar soft part sarcoma: A Turkish Oncology Group (TOG) study. Sci Rep. 2025;15:44124. doi:10.1038/s41598-025-29276-9.\u003c/li\u003e\n\u003cli\u003eHindi N, Razak A, Rosenbaum E, Jonczak E, Hamacher R, Rutkowski P, et al. Efficacy of immune checkpoint inhibitors in alveolar soft-part sarcoma: results from a retrospective worldwide registry. ESMO Open. 2023;8:102045. doi:10.1016/j.esmoop.2023.102045.\u003c/li\u003e\n\u003cli\u003eAtkins MB, Plimack ER, Puzanov I, Fishman MN, McDermott DF, Cho DC, et al. Axitinib in combination with pembrolizumab in patients with advanced renal cell cancer: a non-randomised, open-label, dose-finding, and dose-expansion phase 1b trial. Lancet Oncol. 2018;19:405\u0026ndash;15. doi:10.1016/S1470-2045(18)30081-0.\u003c/li\u003e\n\u003cli\u003eWilky BA, Trucco MM, Subhawong TK, Florou V, Park W, Kwon D, et al. Axitinib plus pembrolizumab in patients with advanced sarcomas including alveolar soft-part sarcoma: a single-centre, single-arm, phase 2 trial. Lancet Oncol. 2019;20:837\u0026ndash;48. doi:10.1016/S1470-2045(19)30153-6.\u003c/li\u003e\n\u003cli\u003eYuan X, Zhou B, Zhong J. Prognostic factors of alveolar soft part sarcoma in children and adolescents: A population-based study. J Stomatol Oral Maxillofac Surg. 2024;125:101852. doi:10.1016/j.jormas.2024.101852.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1 to 4 are available in the supplementary files section\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":false,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-surgical-oncology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjso","sideBox":"Learn more about [World Journal of Surgical Oncology](http://wjso.biomedcentral.com)","snPcode":"12957","submissionUrl":"https://submission.nature.com/new-submission/12957/3","title":"World Journal of Surgical Oncology","twitterHandle":"@OncoBioMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"alveolar soft part sarcoma, spine, en-bloc resection, immunotherapy, prognosis, overall survival","lastPublishedDoi":"10.21203/rs.3.rs-9504084/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9504084/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eSpinal alveolar soft part sarcoma (ASPS) is exceptionally rare, and evidence regarding its optimal management remains limited. This study aimed to describe the clinical and radiological features of spinal ASPS, assess treatment patterns, and identify factors associated with overall survival.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe retrospectively reviewed 20 patients with spinal ASPS who underwent surgery at a single center between 2012 and 2023. Demographic, clinical, radiological, surgical, pathological, and adjuvant treatment data were collected. Survival was analyzed using the Kaplan\u0026ndash;Meier method, and prognostic factors were evaluated using univariate and multivariate Cox regression analyses.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe cohort included 17 males and 3 females, with a mean age of 33.95 years. Fourteen patients (70.0%) had metastatic disease, including 12 before surgery and 2 after surgery. All patients underwent posterior tumor resection and spinal reconstruction; 12 underwent en-bloc resection and 8 underwent subtotal resection. Mean intraoperative blood loss was 2400 mL, and 16 patients required transfusion. Early postoperative evaluation showed significant symptomatic or neurological improvement in 11 patients (55.0%), partial improvement in 4 (20.0%), stable or limited change in 4 (20.0%), and neurological deterioration in 1 (5.0%). During a mean follow-up of 33.15 months, 9 patients were alive and 11 had died. Median overall survival was 28.0 months. Univariate radiological analysis showed that tumor boundary clarity (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), enhancement uniformity (P\u0026thinsp;=\u0026thinsp;0.013), and T2-weighted signal intensity (P\u0026thinsp;=\u0026thinsp;0.032) were significantly associated with prognosis. Multivariate analysis identified postoperative immunotherapy (HR\u0026thinsp;=\u0026thinsp;0.092, P\u0026thinsp;=\u0026thinsp;0.039) and better preoperative neurological status (Frankel grade D\u0026ndash;E; HR\u0026thinsp;=\u0026thinsp;0.079, P\u0026thinsp;=\u0026thinsp;0.006) as independent protective factors, whereas en-bloc resection showed a favorable survival trend (HR\u0026thinsp;=\u0026thinsp;0.236, P\u0026thinsp;=\u0026thinsp;0.070).\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eSpinal ASPS is a highly vascular and surgically demanding malignancy with a substantial metastatic burden. Preoperative tissue diagnosis and selective embolization should be considered when appropriate. En-bloc resection may offer oncological benefit in selected patients, and postoperative immunotherapy was associated with improved survival in this cohort.\u003c/p\u003e\u003ch2\u003eTrial registration\u003c/h2\u003e \u003cp\u003eNot applicable.\u003c/p\u003e","manuscriptTitle":"Clinical Characteristics, Radiological Findings, Treatment Patterns, and Prognostic Factors in Spinal Alveolar Soft Part Sarcoma: A Retrospective Study of 20 Patients","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-15 09:40:00","doi":"10.21203/rs.3.rs-9504084/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2026-05-06T09:38:18+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-05-02T06:27:04+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-27T09:32:00+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Surgical Oncology","date":"2026-04-23T08:19:09+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-surgical-oncology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjso","sideBox":"Learn more about [World Journal of Surgical Oncology](http://wjso.biomedcentral.com)","snPcode":"12957","submissionUrl":"https://submission.nature.com/new-submission/12957/3","title":"World Journal of Surgical Oncology","twitterHandle":"@OncoBioMed","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d97030b5-26d9-4a7f-a243-b04dd1e1e3c7","owner":[],"postedDate":"May 15th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewersInvited","content":"40","date":"2026-05-06T09:38:18+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-05-02T06:27:04+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-15T09:40:00+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-15 09:40:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9504084","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9504084","identity":"rs-9504084","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}