Sequential CT imaging tracing the progression of primary pulmonary mesenchymal chondrosarcoma arising from the wall of a pulmonary cyst: A case report

Sequential CT imaging tracing the progression of primary pulmonary mesenchymal chondrosarcoma arising from the wall of a pulmonary cyst: A case report | 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 Case Report Sequential CT imaging tracing the progression of primary pulmonary mesenchymal chondrosarcoma arising from the wall of a pulmonary cyst: A case report Yoshiaki Inoue, Masatoshi Yamaguchi, Ato Sugiyama, Kohei Aoki, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6638133/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract Background Mesenchymal chondrosarcoma (MC) is a rare, aggressive malignant tumour originating from chondroprogenitor cells and accounts for approximately 3–10% of all chondrosarcomas. MC typically arises within the axial skeleton or soft tissues; primary pulmonary MC is exceedingly rare. Case presentation We describe a rare case of primary pulmonary MC arising from a pulmonary cyst in a 58-year-old male with a 38 pack-year smoking history and bilateral bullectomy performed over 30 years previously. Computed tomography (CT) revealed progressive thickening of a cyst wall lesion in the right apical lung. Positron emission tomography with fluorodeoxyglucose (FDG-PET) revealed mildly increased uptake (SUVmax = 2.18); bronchoscopic cytology indicated class III atypical cells, which led to the initial suspicion of lung cancer. Video-assisted thoracoscopic right upper lobectomy with lymph node dissection was performed. Histopathology revealed a biphasic tumour comprising small round cells and cartilaginous differentiation, which was consistent with MC. This is the first reported case clearly demonstrating the progression of primary pulmonary MC on sequential CT scans. Conclusions We successfully documented the rare progression of primary pulmonary mesenchymal chondrosarcoma from an initially benign pulmonary cyst to a malignant tumour via sequential CT scans over a 14-month period. These finding from sequential imaging examinations highlight the crucial role of continuous radiological follow-up, enabling early recognition, accurate diagnosis, and timely surgical intervention for rare pulmonary malignancies. Mesenchymal chondrosarcoma pulmonary cyst thoracic surgery case report Figures Figure 1 Figure 2 Figure 3 Introduction A 58-year-old male patient presented with a progressively thickening cystic lesion in the right upper lung, which was identified on a CT scan performed during a detailed evaluation for emphysema. His medical history included bilateral pneumothorax treated surgically with bilateral bullectomy via median sternotomy more than 30 years prior and significant emphysema related to a 38-pack-year smoking history. No relevant medication or family history was reported. Clinical course Follow-up CT scans at 3 and 14 months revealed significant and gradual growth of the cyst wall lesion, which was approximately 15 mm thick and 55 mm long upon the patient’s admission to our hospital (Fig. 1 ). FDG-PET imaging revealed mild FDG uptake (SUVmax = 2.18) without evidence of metastatic disease (Fig. 2 ). Bronchoscopic cytology revealed class III atypical cells, initially raising suspicion of primary lung cancer. The patient underwent video-assisted thoracoscopic right upper lobectomy and lymph node dissection (ND2a-1). The surgical margins were negative, and the postoperative course was uneventful. At the one-year follow-up, the patient was alive and disease free with no evidence of recurrence on follow-up imaging. Pathology findings Gross examination revealed a solid, white, homogeneous tumour measuring 6.0 × 4.0 × 2.0 cm from the cyst wall in an emphysematous lung with multiple bullae (Fig. 3 a). Haematoxylin and eosin staining revealed that the tumour consisted of two components: one area with a mass of proliferating small round cells and another area resembling cartilage (Fig. 3 b). The transition zones between these two components were indistinct (Fig. 3 c). The immunohistochemical staining results are detailed in Table 1 . Table 1 Immune staining results S-100 + p63 - GFAP - αSMA - CK AE1/AE3 - CK 7 -, focal+ CK 5/6 - CK 20 - CAM 5.2 + p40 - TTF-1 - Napsin A - S-100: S-100 protein, p63: Tumor protein 63, GAFP: Glial fibrillary acidic protein, αSMA: Alpha smooth muscle actin, CK AE1/AE3: Cytokeratin cocktail AE1/AE3, CK-7: Cytokeratin 7, CK 5/6: Cytokeratin 5/6, CK 20: Cytokeratin 20, CAM 5.2: Cytokeratin antibody (targets CK8/18), p40: ΔNp63 isoform of p63, TTF-1: Thyroid transcription factor-1 The Ki-67 proliferation index was high (80%). No gene fusions, including the characteristic HEY1::NCOA2 fusion, were detected via NCOA2 FISH, EWSR1 FISH or FusionPlex Sarcoma Panel V2 (IDT, Iowa, USA) assessments. Discussion Mesenchymal chondrosarcoma (MC), first described by Lichtenstein in 1959 ( 1 ), accounts for approximately 3–10% of all chondrosarcomas ( 2 , 3 ). Although it is typically diagnosed in adolescents and young adults, it can occur at any age ( 4 , 5 ). Compared with conventional chondrosarcomas, MCs exhibit more aggressive behaviour and have a poorer prognosis and greater metastatic potential, with reported 5-year and 10-year survival rates of 54.6% and 27.3%, respectively ( 5 ). Extraskeletal mesenchymal chondrosarcoma (EMC) accounts for approximately 30% of MC cases ( 6 , 7 , 8 ) and frequently affects the axial bones, ribs, pelvis, and craniofacial regions ( 5 ). Compared with conventional chondrosarcomas, primary MCs more often arise in the axial and appendicular skeleton and at extraosseous sites ( 9 ). Lung cancer arising from the wall of a pulmonary cyst is a rare clinical entity that can mimic benign cystic disease. However, Sabloff et al. reported that individuals with pulmonary bullous disease have an approximately 32-fold increased risk of developing lung cancer compared with those without bullous disease ( 10 ). One proposed pathogenic mechanism involves limited airflow and chronic compression of adjacent pulmonary parenchyma and connective tissues surrounding bullae, which may facilitate the deposition of microorganisms and carcinogens on the cyst walls. The resulting chronic inflammation may subsequently trigger malignant transformation within these cystic lesions ( 11 , 12 ). Although adenocarcinoma is the most frequently described histological subtype arising from pulmonary cysts ( 13 , 14 ), other pathological types, including squamous cell carcinoma, large cell carcinoma, and small cell carcinoma, have also been reported ( 15 , 16 , 17 , 18 ). However, MC arising from a pulmonary cyst has not been previously reported. Primary pulmonary MC is exceedingly rare, with only three cases reported in the English literature ( 19 , 20 , 21 ). Notably, these case reports lacked detailed descriptions of fusion gene analyses or clear evidence of pulmonary origin. This case report is distinctive because of the clear documentation of tumour progression from an initial thin cystic lesion to a substantially thickened tumour mass over 14 months via sequential CT scans, representing the first such report to date. Standard treatment guidelines for pulmonary MC remain undefined; however, complete surgical resection with adjuvant chemotherapy is currently advocated as standard practice ( 5 ). HEY1::NCOA2 fusion is a commonly described genetic abnormality that aids in MC diagnosis ( 22 ). As observed in this case, the absence of this fusion gene underscores the molecular heterogeneity of MCs. These findings emphasize the diagnostic importance of characteristic histopathological and immunohistochemical features. Similar cases, such as a primary renal MC lacking both HEY1::NCOA2 and IRF2BP2::CDX1 fusions, support the existence of multiple genetic pathways underlying MC pathogenesis ( 23 ). While the absence of fusion genes complicates molecular diagnosis, typical histological features remain pivotal for confirming the diagnosis ( 22 ). This case highlights the diagnostic challenge and importance of maintaining a high degree of clinical suspicion of rare tumours presenting as progressive cystic lung lesions; this case also highlights the need for continued research into alternative molecular markers. Conclusions Tracing of the progression of primary pulmonary mesenchymal chondrosarcoma by CT imaging is exceptionally rare because of the infrequent occurrence of this type of tumour. This case report highlights the unique opportunity to observe the step-by-step transformation from a slightly thick pulmonary cyst to an aggressive rare malignancy and highlights the importance of careful imaging-based surveillance for early detection and surgical intervention for rare pulmonary lesions. Abbreviations MC Mesenchymal chondrosarcoma Declarations Ethics approval and consent to participate Written informed consent was obtained from the patient for the publication of this case report and the included clinical information. The authors confirm that all efforts were made to preserve the patient’s anonymity, and no identifying information is included in the manuscript. The study was performed in accordance with the ethical standards outlined by the Declaration of Helsinki. Consent for publication Written informed consent for the publication of this case report and any accompanying images was obtained from the patient. Competing interests The authors declare that they have no competing interests. Funding Not applicable Author Contribution Y.I. wrote the original draft. All authors reviewed and edited the manuscript. Acknowledgement Noriko Motoi and Hiroaki KandaDepartment of Pathological Diagnosis, Saitama Prefecture Cancer Center, Saitama, Japan Data Availability Data is provided within the manuscript. References Lichenstein L, Bernstein D. Unusual benign and malignant chondroid tumors of bone: a survey of some mesenchymal cartilage tumors and malignant chondroblastic tumors, including a few multicentric ones, as well as many atypical benign chondroblastomas and chondromyxoid fibromas. Cancer. 1959;12:1142–57. Bertoni F, Picci P, Bacchini P, Capanna R, Innao V, Bacci G, et al. Mesenchymal chondrosarcoma of bone and soft tissues. Cancer. 1983;52(3):533–41. Nakashima Y, Unni KK, Shives TC, Swee RG, Dahlin DC. Mesenchymal chondrosarcoma of bone and soft tissue: a review of 111 cases. Cancer. 1986;57(12):2444–53. Frezza AM, Cesari M, Baumhoer D, Biau D, Sydow V, Wunder JS, et al. Mesenchymal chondrosarcoma: prognostic factors and outcome in 113 patients. A European Musculoskeletal Oncology Society study. Eur J Cancer. 2015;51(3):374–81. Stanbouly D, Litman E, Vasilyeva D, Gordon SC, McHenry CR, Cervenka B, et al. Mesenchymal chondrosarcoma in the maxilla: a case report and literature review. J Oral Maxillofac Surg. 2021;79(8):1706–11. Arora K, Riddle ND. Extraskeletal mesenchymal chondrosarcoma. Arch Pathol Lab Med. 2018;142(11):1421–4. Chhabra R, Tripathi M, Patra DP, Nanda A, Jaiswal G, Mehta VS, et al. Primary intracranial extraskeletal mesenchymal chondrosarcoma: clinical mimicry as glomus jugulare. Ann Neurosci. 2017;24(3):181–6. Chhabra R, Tripathi M, Patra DP, Nanda A, Jaiswal G, Mehta VS, et al. Primary intracranial extraskeletal mesenchymal chondrosarcoma: clinical mimicry as glomus jugulare. Ann Neurosci. 2017;24(3):181–6. Strach MC, Grimison PS, Hong A, Brennan ME, Spruyt O, Boyle FM, et al. Mesenchymal chondrosarcoma: an Australian multi-centre cohort study. Cancer Med. 2023;12(1):368–78. Stoloff IL, Kanofsky P, Magilner L. The risk of lung cancer in males with bullous disease of the lung. Arch Environ Health. 1971;22(1):163–7. Farooqi AO, Cham M, Zhang L, Beasley MB, Austin JH, Miller A, et al. Lung cancer associated with cystic airspaces. AJR Am J Roentgenol. 2012;199:781–6. Wang K, Leng X, Yi H, Zhang G, Hu Z, Mao Y. Lung cancer associated with cystic airspaces: current insights into diagnosis, pathophysiology, and treatment strategies. Cancers (Basel). 2024;16(23):3930. Liu Z, Zhang ZR, Sun HL, Zhang L, Zhang J, Zheng X, et al. CT and clinicopathological features of thin-walled cystic lung cancer with the largest diameter less than or equal to 3 cm. Chin J Clin Thorac Cardiovasc Surg. 2019;26:1074–8. Pan X, Wang H, Yu H, Chen Z, Wang Z, Wang L, et al. Lung cancer associated with cystic airspaces: CT and pathological features. Transl Cancer Res. 2020;9(6):3960–4. Usui S, Minami Y, Shiozawa T, Inoue T, Morita T, Sugimoto Y, et al. Differences in the prognostic implications of vascular invasion between lung adenocarcinoma and squamous cell carcinoma. Lung Cancer. 2013;82:407–12. Lei Y, Wu Y. The prognostic value of micrometastasis in non-small cell lung cancer. Zhongguo Fei Ai Za Zhi. 2013;16:492–8. Igai H, Tarumi S, Chang SS, Yokomise H. Predictor of intrathoracic lymph node metastasis in peripheral non-small cell lung cancers 20 mm or less in greatest dimension. Kyobu Geka. 2012;65:175–83. Wang Y, Fan L, Liu SY. Advances in imaging and pathological studies on cystic airspaces-containing peripheral lung cancer. J Clin Radiol. 2016;35:486–9. Huang HY, Hsieh MJ, Chen WJ, Ko SF, Yang BY, Huang SC. Primary mesenchymal chondrosarcoma of the lung. Ann Thorac Surg. 2002;73(6):1960–2. Mei B, Lai YL, He GJ, Shou YN, Liu J. Giant primary mesenchymal chondrosarcoma of the lung: case report and review of literature. Ann Thorac Cardiovasc Surg. 2013;19(6):481–4. Perry WR, McHugh JB, Konopka KE. Primary mesenchymal chondrosarcoma of the lung. Pathol Int. 2023;73(4):170–2. Dudzisz-Śledź M, Kondracka M, Rudzińska M, Niewiadomska E, Lugowska I, Szumera-Ciećkiewicz A, et al. Mesenchymal chondrosarcoma from diagnosis to clinical trials. Cancers (Basel). 2023;15(18):4581. Yamagishi A, Ichiyanagi O, Naito M, Maeda S, Yamazaki H, Kitahara H, et al. Primary mesenchymal chondrosarcoma of the kidney without HEY1-NCOA2 and IRF2BP2-CDX1 fusion: a case report and review. Oncol Lett. 2020;19(1):885–91. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 13 Jul, 2025 Reviewers agreed at journal 13 Jul, 2025 Reviews received at journal 27 Jun, 2025 Reviewers agreed at journal 25 Jun, 2025 Reviewers invited by journal 24 Jun, 2025 Editor assigned by journal 18 Jun, 2025 Editor invited by journal 26 May, 2025 Submission checks completed at journal 24 May, 2025 First submitted to journal 24 May, 2025 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. 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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-6638133","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":476112744,"identity":"9355fa15-8900-4f3f-af5f-103d0a6b82a9","order_by":0,"name":"Yoshiaki 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07:08:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6638133/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6638133/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85647537,"identity":"b1d45f7a-d09f-44c7-860a-84491aa9815c","added_by":"auto","created_at":"2025-06-30 08:48:59","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":950063,"visible":true,"origin":"","legend":"\u003cp\u003eFollow-up CT scan images at baseline (a and b), 3 months (c and d), and 14 months (e and f) show progressive thickening of the cyst wall in the left upper lobe.\u003c/p\u003e","description":"","filename":"floatimage1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6638133/v1/ea70107ddf777df7c8dd6a90.jpeg"},{"id":85647536,"identity":"67d4363a-8ccd-42ad-b85a-e0abc9eb89b2","added_by":"auto","created_at":"2025-06-30 08:48:59","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":316658,"visible":true,"origin":"","legend":"\u003cp\u003eFDG-PET imaging revealed the accumulation of FDG (SUVmax = 2.18).\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6638133/v1/5a90bfd0f3d97b14b7f6ddfd.jpeg"},{"id":85647540,"identity":"4959da73-ad92-4965-8498-31211e230598","added_by":"auto","created_at":"2025-06-30 08:48:59","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":799505,"visible":true,"origin":"","legend":"\u003cp\u003eBased on emphysema, a 6.0 x 4.0 x 2.0 cm white solid tumour arose in the cyst wall (a).\u003c/p\u003e\n\u003cp\u003eThe tumour consisted of two components: a mass of small round cells and an area resembling cartilage (b). Some regions showed no border between these two components (c).\u003c/p\u003e","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6638133/v1/5e1d7f7df04dacf9f09fb777.jpeg"},{"id":85649820,"identity":"a815fe5c-f359-40f2-9c60-91ac2925ea2f","added_by":"auto","created_at":"2025-06-30 09:05:00","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2531138,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6638133/v1/4d04fc4c-1e43-446b-96b1-22a2118f5de8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Sequential CT imaging tracing the progression of primary pulmonary mesenchymal chondrosarcoma arising from the wall of a pulmonary cyst: A case report","fulltext":[{"header":"Introduction","content":"\u003cp\u003eA 58-year-old male patient presented with a progressively thickening cystic lesion in the right upper lung, which was identified on a CT scan performed during a detailed evaluation for emphysema. His medical history included bilateral pneumothorax treated surgically with bilateral bullectomy via median sternotomy more than 30 years prior and significant emphysema related to a 38-pack-year smoking history. No relevant medication or family history was reported.\u003c/p\u003e\n\u003ch3\u003eClinical course\u003c/h3\u003e\n\u003cp\u003eFollow-up CT scans at 3 and 14 months revealed significant and gradual growth of the cyst wall lesion, which was approximately 15 mm thick and 55 mm long upon the patient’s admission to our hospital (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). FDG-PET imaging revealed mild FDG uptake (SUVmax = 2.18) without evidence of metastatic disease (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Bronchoscopic cytology revealed class III atypical cells, initially raising suspicion of primary lung cancer. The patient underwent video-assisted thoracoscopic right upper lobectomy and lymph node dissection (ND2a-1). The surgical margins were negative, and the postoperative course was uneventful. At the one-year follow-up, the patient was alive and disease free with no evidence of recurrence on follow-up imaging.\u003c/p\u003e"},{"header":"Pathology findings","content":"\u003cp\u003eGross examination revealed a solid, white, homogeneous tumour measuring 6.0 × 4.0 × 2.0 cm from the cyst wall in an emphysematous lung with multiple bullae (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea).\u003c/p\u003e\u003cp\u003eHaematoxylin and eosin staining revealed that the tumour consisted of two components: one area with a mass of proliferating small round cells and another area resembling cartilage (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb). The transition zones between these two components were indistinct (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ec). The immunohistochemical staining results are detailed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eImmune staining results\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e\u003ccolgroup cols=\"2\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eS-100\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e+\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ep63\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGFAP\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eαSMA\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCK AE1/AE3\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCK 7\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-, focal+\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCK 5/6\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCK 20\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCAM 5.2\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e+\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ep40\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTTF-1\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNapsin A\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e\u003cp\u003eS-100: S-100 protein, p63: Tumor protein 63, GAFP: Glial fibrillary acidic protein, αSMA: Alpha smooth muscle actin, CK AE1/AE3: Cytokeratin cocktail AE1/AE3, CK-7: Cytokeratin 7, CK 5/6: Cytokeratin 5/6, CK 20: Cytokeratin 20, CAM 5.2: Cytokeratin antibody (targets CK8/18), p40: ΔNp63 isoform of p63, TTF-1: Thyroid transcription factor-1\u003c/p\u003e\u003cp\u003eThe Ki-67 proliferation index was high (80%).\u003c/p\u003e\u003cp\u003eNo gene fusions, including the characteristic \u003cem\u003eHEY1::NCOA2\u003c/em\u003e fusion, were detected via NCOA2 FISH, EWSR1 FISH or FusionPlex Sarcoma Panel V2 (IDT, Iowa, USA) assessments.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eMesenchymal chondrosarcoma (MC), first described by Lichtenstein in 1959 (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e), accounts for approximately 3\u0026ndash;10% of all chondrosarcomas (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Although it is typically diagnosed in adolescents and young adults, it can occur at any age (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Compared with conventional chondrosarcomas, MCs exhibit more aggressive behaviour and have a poorer prognosis and greater metastatic potential, with reported 5-year and 10-year survival rates of 54.6% and 27.3%, respectively (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eExtraskeletal mesenchymal chondrosarcoma (EMC) accounts for approximately 30% of MC cases (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) and frequently affects the axial bones, ribs, pelvis, and craniofacial regions (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Compared with conventional chondrosarcomas, primary MCs more often arise in the axial and appendicular skeleton and at extraosseous sites (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Lung cancer arising from the wall of a pulmonary cyst is a rare clinical entity that can mimic benign cystic disease. However, Sabloff et al. reported that individuals with pulmonary bullous disease have an approximately 32-fold increased risk of developing lung cancer compared with those without bullous disease (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eOne proposed pathogenic mechanism involves limited airflow and chronic compression of adjacent pulmonary parenchyma and connective tissues surrounding bullae, which may facilitate the deposition of microorganisms and carcinogens on the cyst walls. The resulting chronic inflammation may subsequently trigger malignant transformation within these cystic lesions (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Although adenocarcinoma is the most frequently described histological subtype arising from pulmonary cysts (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e), other pathological types, including squamous cell carcinoma, large cell carcinoma, and small cell carcinoma, have also been reported (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). However, MC arising from a pulmonary cyst has not been previously reported.\u003c/p\u003e \u003cp\u003ePrimary pulmonary MC is exceedingly rare, with only three cases reported in the English literature (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e). Notably, these case reports lacked detailed descriptions of fusion gene analyses or clear evidence of pulmonary origin. This case report is distinctive because of the clear documentation of tumour progression from an initial thin cystic lesion to a substantially thickened tumour mass over 14 months via sequential CT scans, representing the first such report to date.\u003c/p\u003e \u003cp\u003eStandard treatment guidelines for pulmonary MC remain undefined; however, complete surgical resection with adjuvant chemotherapy is currently advocated as standard practice (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cem\u003eHEY1::NCOA2\u003c/em\u003e fusion is a commonly described genetic abnormality that aids in MC diagnosis (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). As observed in this case, the absence of this fusion gene underscores the molecular heterogeneity of MCs. These findings emphasize the diagnostic importance of characteristic histopathological and immunohistochemical features. Similar cases, such as a primary renal MC lacking both \u003cem\u003eHEY1::NCOA2 and IRF2BP2::CDX1\u003c/em\u003e fusions, support the existence of multiple genetic pathways underlying MC pathogenesis (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e). While the absence of fusion genes complicates molecular diagnosis, typical histological features remain pivotal for confirming the diagnosis (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). This case highlights the diagnostic challenge and importance of maintaining a high degree of clinical suspicion of rare tumours presenting as progressive cystic lung lesions; this case also highlights the need for continued research into alternative molecular markers.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eTracing of the progression of primary pulmonary mesenchymal chondrosarcoma by CT imaging is exceptionally rare because of the infrequent occurrence of this type of tumour. This case report highlights the unique opportunity to observe the step-by-step transformation from a slightly thick pulmonary cyst to an aggressive rare malignancy and highlights the importance of careful imaging-based surveillance for early detection and surgical intervention for rare pulmonary lesions.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eMC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eMesenchymal chondrosarcoma\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\u003eWritten informed consent was obtained from the patient for the publication of this case report and the included clinical information. The authors confirm that all efforts were made to preserve the patient\u0026rsquo;s anonymity, and no identifying information is included in the manuscript. The study was performed in accordance with the ethical standards outlined by the Declaration of Helsinki.\u003c/p\u003e\n\u003ch2\u003eConsent for publication\u003c/h2\u003e\n\u003cp\u003eWritten informed consent for the publication of this case report and any accompanying images was obtained from the patient.\u003c/p\u003e\n\u003ch2\u003eCompeting interests\u003c/h2\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eY.I. wrote the original draft. All authors reviewed and edited the manuscript.\u003c/p\u003e\n\u003ch2\u003eAcknowledgement\u003c/h2\u003e\n\u003cp\u003eNoriko Motoi and Hiroaki KandaDepartment of Pathological Diagnosis, Saitama Prefecture Cancer Center, Saitama, Japan\u003c/p\u003e\n\u003ch2\u003eData Availability\u003c/h2\u003e\n\u003cp\u003eData is provided within the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLichenstein L, Bernstein D. Unusual benign and malignant chondroid tumors of bone: a survey of some mesenchymal cartilage tumors and malignant chondroblastic tumors, including a few multicentric ones, as well as many atypical benign chondroblastomas and chondromyxoid fibromas. Cancer. 1959;12:1142\u0026ndash;57.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBertoni F, Picci P, Bacchini P, Capanna R, Innao V, Bacci G, et al. Mesenchymal chondrosarcoma of bone and soft tissues. Cancer. 1983;52(3):533\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNakashima Y, Unni KK, Shives TC, Swee RG, Dahlin DC. Mesenchymal chondrosarcoma of bone and soft tissue: a review of 111 cases. Cancer. 1986;57(12):2444\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFrezza AM, Cesari M, Baumhoer D, Biau D, Sydow V, Wunder JS, et al. Mesenchymal chondrosarcoma: prognostic factors and outcome in 113 patients. A European Musculoskeletal Oncology Society study. Eur J Cancer. 2015;51(3):374\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStanbouly D, Litman E, Vasilyeva D, Gordon SC, McHenry CR, Cervenka B, et al. Mesenchymal chondrosarcoma in the maxilla: a case report and literature review. J Oral Maxillofac Surg. 2021;79(8):1706\u0026ndash;11.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eArora K, Riddle ND. Extraskeletal mesenchymal chondrosarcoma. Arch Pathol Lab Med. 2018;142(11):1421\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChhabra R, Tripathi M, Patra DP, Nanda A, Jaiswal G, Mehta VS, et al. Primary intracranial extraskeletal mesenchymal chondrosarcoma: clinical mimicry as glomus jugulare. Ann Neurosci. 2017;24(3):181\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChhabra R, Tripathi M, Patra DP, Nanda A, Jaiswal G, Mehta VS, et al. Primary intracranial extraskeletal mesenchymal chondrosarcoma: clinical mimicry as glomus jugulare. Ann Neurosci. 2017;24(3):181\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStrach MC, Grimison PS, Hong A, Brennan ME, Spruyt O, Boyle FM, et al. Mesenchymal chondrosarcoma: an Australian multi-centre cohort study. Cancer Med. 2023;12(1):368\u0026ndash;78.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStoloff IL, Kanofsky P, Magilner L. The risk of lung cancer in males with bullous disease of the lung. Arch Environ Health. 1971;22(1):163\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFarooqi AO, Cham M, Zhang L, Beasley MB, Austin JH, Miller A, et al. Lung cancer associated with cystic airspaces. AJR Am J Roentgenol. 2012;199:781\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang K, Leng X, Yi H, Zhang G, Hu Z, Mao Y. Lung cancer associated with cystic airspaces: current insights into diagnosis, pathophysiology, and treatment strategies. Cancers (Basel). 2024;16(23):3930.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiu Z, Zhang ZR, Sun HL, Zhang L, Zhang J, Zheng X, et al. CT and clinicopathological features of thin-walled cystic lung cancer with the largest diameter less than or equal to 3 cm. Chin J Clin Thorac Cardiovasc Surg. 2019;26:1074\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePan X, Wang H, Yu H, Chen Z, Wang Z, Wang L, et al. Lung cancer associated with cystic airspaces: CT and pathological features. Transl Cancer Res. 2020;9(6):3960\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUsui S, Minami Y, Shiozawa T, Inoue T, Morita T, Sugimoto Y, et al. Differences in the prognostic implications of vascular invasion between lung adenocarcinoma and squamous cell carcinoma. Lung Cancer. 2013;82:407\u0026ndash;12.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLei Y, Wu Y. The prognostic value of micrometastasis in non-small cell lung cancer. Zhongguo Fei Ai Za Zhi. 2013;16:492\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIgai H, Tarumi S, Chang SS, Yokomise H. Predictor of intrathoracic lymph node metastasis in peripheral non-small cell lung cancers 20 mm or less in greatest dimension. Kyobu Geka. 2012;65:175\u0026ndash;83.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang Y, Fan L, Liu SY. Advances in imaging and pathological studies on cystic airspaces-containing peripheral lung cancer. J Clin Radiol. 2016;35:486\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHuang HY, Hsieh MJ, Chen WJ, Ko SF, Yang BY, Huang SC. Primary mesenchymal chondrosarcoma of the lung. Ann Thorac Surg. 2002;73(6):1960\u0026ndash;2.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMei B, Lai YL, He GJ, Shou YN, Liu J. Giant primary mesenchymal chondrosarcoma of the lung: case report and review of literature. Ann Thorac Cardiovasc Surg. 2013;19(6):481\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePerry WR, McHugh JB, Konopka KE. Primary mesenchymal chondrosarcoma of the lung. Pathol Int. 2023;73(4):170\u0026ndash;2.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDudzisz-Śledź M, Kondracka M, Rudzińska M, Niewiadomska E, Lugowska I, Szumera-Ciećkiewicz A, et al. Mesenchymal chondrosarcoma from diagnosis to clinical trials. Cancers (Basel). 2023;15(18):4581.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYamagishi A, Ichiyanagi O, Naito M, Maeda S, Yamazaki H, Kitahara H, et al. Primary mesenchymal chondrosarcoma of the kidney without HEY1-NCOA2 and IRF2BP2-CDX1 fusion: a case report and review. Oncol Lett. 2020;19(1):885\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e\u003c/ol\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":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pulmonary-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pulm","sideBox":"Learn more about [BMC Pulmonary Medicine](http://bmcpulmmed.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pulm/default.aspx","title":"BMC Pulmonary Medicine","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Mesenchymal chondrosarcoma, pulmonary cyst, thoracic surgery, case report","lastPublishedDoi":"10.21203/rs.3.rs-6638133/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6638133/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eMesenchymal chondrosarcoma (MC) is a rare, aggressive malignant tumour originating from chondroprogenitor cells and accounts for approximately 3\u0026ndash;10% of all chondrosarcomas. MC typically arises within the axial skeleton or soft tissues; primary pulmonary MC is exceedingly rare.\u003c/p\u003e\u003ch2\u003eCase presentation\u003c/h2\u003e \u003cp\u003eWe describe a rare case of primary pulmonary MC arising from a pulmonary cyst in a 58-year-old male with a 38 pack-year smoking history and bilateral bullectomy performed over 30 years previously. Computed tomography (CT) revealed progressive thickening of a cyst wall lesion in the right apical lung. Positron emission tomography with fluorodeoxyglucose (FDG-PET) revealed mildly increased uptake (SUVmax\u0026thinsp;=\u0026thinsp;2.18); bronchoscopic cytology indicated class III atypical cells, which led to the initial suspicion of lung cancer. Video-assisted thoracoscopic right upper lobectomy with lymph node dissection was performed. Histopathology revealed a biphasic tumour comprising small round cells and cartilaginous differentiation, which was consistent with MC. This is the first reported case clearly demonstrating the progression of primary pulmonary MC on sequential CT scans.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eWe successfully documented the rare progression of primary pulmonary mesenchymal chondrosarcoma from an initially benign pulmonary cyst to a malignant tumour via sequential CT scans over a 14-month period. These finding from sequential imaging examinations highlight the crucial role of continuous radiological follow-up, enabling early recognition, accurate diagnosis, and timely surgical intervention for rare pulmonary malignancies.\u003c/p\u003e","manuscriptTitle":"Sequential CT imaging tracing the progression of primary pulmonary mesenchymal chondrosarcoma arising from the wall of a pulmonary cyst: A case report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-30 08:48:54","doi":"10.21203/rs.3.rs-6638133/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2025-07-14T03:30:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"254631752493496395112281655361391035524","date":"2025-07-14T01:55:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-27T15:49:48+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"56812340904250775245042495955331429314","date":"2025-06-25T06:32:48+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-24T11:33:20+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-18T15:16:48+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-05-26T08:36:09+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-24T05:31:36+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pulmonary Medicine","date":"2025-05-24T05:30:28+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pulmonary-medicine","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pulm","sideBox":"Learn more about [BMC Pulmonary Medicine](http://bmcpulmmed.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pulm/default.aspx","title":"BMC Pulmonary Medicine","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"cace3c70-ea6e-4d8b-8f2b-4f48f50929c7","owner":[],"postedDate":"June 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-06-30T08:48:54+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-30 08:48:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6638133","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6638133","identity":"rs-6638133","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}