A Case-control Study of MRI Features in Pediatric Atypical Teratoid Rhabdoid Tumor and Medulloblastoma

A Case-control Study of MRI Features in Pediatric Atypical Teratoid Rhabdoid Tumor and Medulloblastoma | 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 A Case-control Study of MRI Features in Pediatric Atypical Teratoid Rhabdoid Tumor and Medulloblastoma Zhiming Yang, Yali Yue, Feixiao Wu, Xihong Hu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9079157/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Background Compared to medulloblastoma (MB), atypical teratoid rhabdoid tumor (AT/RT) is characterized by a lower incidence, younger age at onset, and a poorer prognosis. Preoperative clinical and neuroimaging differentiation between these tumors remains challenging. This study aimed to evaluate the diagnostic utility of conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in distinguishing AT/RT from MB in children. Methods We retrospectively included 32 patients with AT/RT and 82 patients with MB confirmed by surgery and pathology in our hospital between 2010 and 2023. We analyzed the clinical data, preoperative MRI characteristics, and apparent diffusion coefficient (ADC) values of these patients to evaluate their diagnostic value. Results The overall survival time of AT/RT patients was significantly shorter than that of MB patients ( P < 0.001), with a higher mortality rate (81.4% vs. 35.5%, P = 0.007). Significant differences were found between AT/RT and MB in T2WI signal, off-midline growth, supratentorial ventriculomegaly, cystic degeneration, hemorrhage, peritumoral edema, tumor boundary clarity, and metastasis/dissemination ( P 0.05). The mean ADC value differed significantly between the two groups ( P < 0.001), with an optimal cut-off value of 0.622 × 10⁻³ mm²/s. Conclusion MRI features, including more cystic degeneration, hemorrhage, supratentorial ventriculomegaly, and peritumoral edema, combined with a lower ADC value may provide reliable information to differentiate AT/RT from MB in children. Atypical teratoid rhabdoid tumor (AT/RT) Brain tumor Magnetic resonance imaging Medulloblastoma (MB) Figures Figure 1 Figure 2 Introduction According to the 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors, atypical teratoid rhabdoid tumor (AT/RT) and medulloblastoma (MB) are classified as embryonic tumors[ 1 ]. Embryonic tumors account for approximately 20% of childhood brain tumors, characterized histologically by dense small round blue cells with scant cytoplasm and varying degrees of differentiation[2; 3]. Medulloblastoma is the most common malignant pediatric brain tumor, representing over 60% of childhood embryonic tumors[ 4 ]. The presence of small round blue cells in about two-thirds of AT/RT cases led to its misdiagnosis as MB[ 5 ]. There are even reported cases where immunohistochemistry confirmed tumors containing both AT/RT and MB components, or where initial pathology was typical for MB but recurrence presented with extraneural metastasis and rhabdoid differentiation[6; 7]. However, AT/RT carries a significantly worse prognosis due to higher malignancy, faster growth, younger age at onset, and greater invasiveness[ 8 ]. Current multimodal treatment involving surgery, radiotherapy, and systemic/intrathecal chemotherapy can achieve long-term survival rates of 60–80% for MB patients and improve the 2-year progression-free and overall survival rates for AT/RT patients to 53% and 70%, respectively[9; 10]. Therefore, accurate preoperative imaging diagnosis is crucial for guiding surgical strategy, planning adjuvant therapy, and improving prognosis. The purpose of this study is to explore the clinical and MRI features that help differentiate AT/RT and MB in pediatric patients, in order to develop appropriate treatment plans and improve patient outcomes. Materials and methods Patients This retrospective study was approved by our Institutional Ethics Review Committee, and informed consent was obtained from the parents or guardians of all patients. A total of 114 patients diagnosed with AT/RT or MB by surgical pathology between January 1, 2010, and June 30, 2023, were enrolled, including 32 AT/RT and 82 MB cases. Clinical data, treatment details (surgery, chemotherapy, radiotherapy), and survival follow-up information were comprehensively reviewed. MR examination protocol Some patients (over 3 years old) cooperated after reassurance. For 69 uncooperative children (under 3 years old: 24 AT/RT, 45 MB), 10% chloral hydrate (0.5 ml/kg) was administered orally or via enema, and imaging proceeded after sleep induction. MRI was performed using a Siemens Magnetom Avanto 1.5T scanner with a head matrix coil. Sequences included non-contrast scans, DWI, and post-contrast scans with the following parameters: slice thickness 5 mm, gap 7 mm, FOV 240 × 240 mm. These included axial and sagittal FLASH T1WI (TR 1450 ms, TE 25 ms), axial TSE T2WI (TR 9000 ms, TE 92 ms), and DWI (TR 5000 ms, TE 65 ms). DWI used b-values of 0 and 1000 s/mm² applied in three orthogonal directions. The contrast agent for enhanced scanning was gadolinium diethylenetriamine pentaacetate (Gd-DTPA) at 0.5 mmol/mL (0.1 mmol/kg). Post-injection, axial and sagittal FLASH T1WI scans were repeated using the same parameters as the pre-contrast scan. On DWI images, regions of interest (ROIs) were carefully placed to avoid areas of hemorrhage, necrosis, or cystic degeneration. Image Analysis and ADC Measurement All images were retrospectively and independently reviewed by two radiologists with over ten years of neuroimaging experience using a Picture Archiving and Communication System (PACS) (GE Healthcare Centricity RIS CE V2.0), blinded to pathological results. Consensus was reached on the following features: off-midline growth, tumor size, signal intensity, enhancement characteristics, supratentorial ventriculomegaly, hemorrhage, cystic degeneration, peritumoral edema, tumor boundary (clear/unclear), peritumoral tissue invasion, and metastasis/dissemination. Off-midline growth was defined as tumor origin outside the fourth ventricle or cerebellar vermis, with the tumor mass entirely located to one side. Peritumoral edema was graded as: none; Grade I (edema extent 100%)[ 11 ]. For ADC measurement, a lesion slice showing relatively homogeneous signal in the solid component was selected. A circular or oval ROI (area: 10–40 mm²) was manually drawn on the corresponding DWI image. Three ROIs were placed at different levels within the solid part of each tumor, and the mean value was recorded as the ADC for that case. Statistical analysis Data were analyzed using SPSS software (version 22.0). For continuous variables (ADC values - min, max, mean; age; tumor size), normality and homogeneity of variance were assessed using the Kolmogorov-Smirnov test and Levene's test, respectively. As these assumptions were not met, the Mann-Whitney U test was employed for group comparisons. The diagnostic performance of the mean ADC was evaluated using receiver operating characteristic (ROC) curve analysis, with the optimal cut-off value determined by the Youden index. Sensitivity and specificity were calculated. Categorical variables (e.g., tumor location, off-midline growth, hemorrhage) were compared using the Pearson Chi-square test. Continuous data are presented as mean ± standard deviation (SD), and categorical data as counts (percentages). A two-sided P value < 0.05 was considered statistically significant. Results Clinical Characteristics The study included 114 children: 32 with AT/RT (20 males, 12 females; age range 4 months-13 years, mean 3.8 ± 4.5 years) and 82 with MB (56 males, 26 females; age range 3 months-13 years, mean 5.6 ± 3.9 years). No significant differences were found in age or gender distribution between the groups ( P = 0.417 and P = 0.658, respectively). During follow-up, 5 AT/RT and 6 MB patients were lost. Among those with complete data, the mean overall survival was significantly shorter for AT/RT (29.3 ± 12.2 months, range 1-85) compared to MB (70.5 ± 14.8 months, range 1-112) ( P < 0.001). Mortality was higher in the AT/RT group (81.4%, 22/27) than in the MB group (35.5%, 27/76) ( P = 0.007). The post-operative recurrence/disease progression rate was significantly higher for AT/RT (85.1%, 23/27) than for MB (38.1%, 29/76) ( P = 0.014). The time from surgery to recurrence/dissemination was also significantly shorter for AT/RT (7.3 ± 11.4 months, range 1-29) than for MB (20.6 ± 17.7 months, range 4-56) ( P = 0.002) (Table 1). Imaging Features The maximum tumor diameter ranged from 17-95 mm (mean 49.2 ± 17.0 mm) for AT/RT and 10-76 mm (mean 44.2 ± 11.1 mm) for MB, with no significant difference ( P = 0.073). Regarding MRI signal intensity, both groups showed predominantly iso- to hypointense or mixed signals on T1WI ( P = 0.83). On T2WI, AT/RT signals were predominantly slightly hyperintense (13 cases) or mixed (13 cases), whereas MB signals were predominantly slightly hyperintense (59 cases) ( P = 0.044). Off-midline growth was significantly more frequent in AT/RT (56.3%, 18/32) than in MB (17.1%, 14/82) ( P = 0.001). MB tumors had clearer boundaries than AT/RT tumors (69.5% vs. 37.5%, P = 0.007) and were associated with a higher incidence of supratentorial ventriculomegaly (97.6% vs. 46.9%, P = 0.001). AT/RT tumors showed a higher prevalence of peritumoral edema (78.1% vs. 37.8%, P = 0.001), intratumoral hemorrhage (31.2% vs. 8.5%, P = 0.024), cystic degeneration (75.0% vs. 37.8%, P = 0.035), and metastasis/dissemination (56.3% vs. 28.0%, P = 0.042). No significant difference was found in enhancement patterns between the groups ( P = 0.223) (Table 2). Characteristic MRI features of AT/RT included off-midline location, markedly heterogeneous or wreath-like enhancement, cystic/necrotic components, hemorrhage, and significant peritumoral edema (Figure 1). MB typically presented as a midline posterior fossa mass causing supratentorial ventriculomegaly (Figure 2). ADC values derived from the solid tumor components showed statistically significant differences between groups for mean ADC, ADCmin, and ADCmax ( P < 0.001 for all). The mean ADC value was significantly lower in the AT/RT group (0.521 ± 0.104 × 10⁻³ mm²/s, range 0.424-0.698) compared to the MB group (0.710 ± 0.094 × 10⁻³ mm²/s, range 0.492-0.956) (Table 3). ROC curve analysis for mean ADC yielded an area under the curve (AUC) of 0.927. The optimal diagnostic cut-off was 0.622 × 10⁻³ mm²/s, providing a sensitivity of 90.1% and specificity of 87.5% for differentiating AT/RT from MB (Table 4). Discussion AT/RT and MB are both classified as WHO CNS grade 4 tumors[1]. AT/RT is a rare, highly aggressive malignant CNS tumor, typically affecting infants and young children under 3 years of age, accounting for 1.6% of CNS tumors in individuals ≤19 years and 10.1% in those under 1 year[12; 13; 11; 14; 15]. Previous studies reported a younger onset age and possible male predominance for AT/RT compared to MB[11; 16]. However, our study found no significant differences in age or gender distribution, noting a recent trend of older female patients (>10 years) within the AT/RT group, suggesting evolving demographic patterns that warrant further investigation. AT/RT is associated with a notably poor prognosis, as reflected in our findings: patients with AT/RT had significantly shorter overall survival, higher mortality and recurrence rates, and a shorter interval from surgery to tumor progression or dissemination compared to those with MB. The current study demonstrates that while maximum safe resection combined with early radiotherapy is a reasonable multi-mode treatment that can prolong the progression-free survival of AT/RT patients, only the degree of resection and adjuvant treatment status have a significant impact on overall survival and event-free survival[17], consequently the purpose of surgery should be to achieve complete resection. In the context of radiogenomics providing opportunities for risk stratification and selection of suitable targeted genetic analysis for MB, there has been the research being conducted by using MRI based machine to learn decision paths allowing for identification of four clinically relevant molecular subgroups of pediatric MB, the accuracy of tumor volume size measurement has also made progress[18; 19]. Therefore, considering the high malignancy of AT/RT, the similarity of the two tumor manifestations, and the differences in treatment, it is essential to differentiate AT/RT and MB. In this study, the incidence of AT/RT non midline growth was 61.9%, with lesions mostly located in the cerebellopontine angle, cerebellar hemisphere, and frontotemporal lobe. Multiple studies have indicated that AT/RT often grows in the cerebellopontine angle, with a higher incidence than other areas[20; 21; 16]. MB is characterized by the growth in the subtentorial midline, with an incidence of only 17.5% of off-midline growth, the difference between the two tumor groups in this study having attained statistical significance. The lesions of MB are mostly located in the fourth ventricle, cerebellar vermis, and other areas, resulting in compression and obstruction of the fourth ventricle, as well as hydrocephalic dilation of the third and lateral ventricles. Therefore, the statistical significance of difference in the incidence of supratentorial ventriculomegaly between the two groups may be related to this. Compared to AT/RT, the lesions of MB are mostly solid or predominantly solid, with relatively infrequent cystic degeneration, necrosis, and hemorrhage[22-24]. In this study, the cystic degeneration rate of different degrees in the AT/RT group was 76.2%, significantly higher than that of the MB group at 37.5%. Hemorrhage is also a significant feature of AT/RT. Previous studies have shown that AT/RT has a higher cerebral blood volume (CBV) value than MB[25], indicating that there is more abundant neovascularization in AT/RT, and the trend to intratumoral hemorrhage of AT/RT may be related to this characteristic. Due to its high malignancy, AT/RT is prone to spreading intracranial along the cerebrospinal fluid to the spinal cord, lateral ventricles, and even brainstem meninges, many studies have reported[22; 24; 26]. In this study, the metastasis and/or dissemination rate of AT/RT was 59.3% (19% in MB). It also showed that MB lesions have clearer boundaries than AT/RT lesions. There is a significant difference in peritumoral edema between the two groups. Peritumoral edema was more frequent and severe in AT/RT, with 57% of cases exhibiting grade II or higher edema, compared to only 22.5% in MB. Perhaps in addition to cytotoxic edema, ischemic edema caused by compression of the tumor and hydrocephalic dilation, the degree of peritumoral edema is also related to the high malignancy of AT/RT, corresponding with previous studies[22; 24; 14]. Although there was no significant difference in the enhancement patterns between the two groups, the AT/RT tumors were mainly mixed solid-cystic, with eccentric large cystic degeneration and annular enhancement of the parenchymal components，of which wreath-like enhancement had previously been shown as a relatively characteristic imaging feature in AT/RT[24]. This type of enhancement appeared in 5 of our cases in the AT/RT group, but not in the MB group. A significant contribution of our study is the quantitative analysis of DWI. The mean ADC value of the solid tumor component was significantly lower in AT/RT (0.521 ± 0.104 × 10⁻³ mm²/s) than in MB (0.710 ± 0.094 × 10⁻³ mm²/s), with an optimal diagnostic cut-off of 0.622 × 10⁻³ mm²/s (AUC=0.927, sensitivity 90.1%, specificity 87.5%). This finding corroborates and extends previous reports[20; 27]. While earlier studies with smaller samples reported overlapping or variable ADC values, our larger cohort provides robust evidence that restricted diffusion is more pronounced in AT/RT. This lower ADC likely reflects higher cellular density and/or nuclear-to-cytoplasmic ratio within AT/RT, correlating with its higher histological grade and aggressive behavior. Notably, Wu et al also found significantly lower ADCmin and ADC ratios in AT/RT compared to MB, and highlighted a higher DWI ratio. This study has several limitations, including its retrospective design, the small cohort of AT/RT patients due to the rarity of the disease, and the absence of advanced MRI techniques such as perfusion imaging and MR spectroscopy. Furthermore, although certain imaging findings showed statistical significance, their diagnostic sensitivity and specificity may not yet be sufficient to replace surgical intervention and pathological confirmation. Conclusion In summary, by combining clinical data to analyze MRI features and DWI parameters, this study can provide relatively reliable information for the differential diagnosis of intracranial AT/RT and MB in children. The specificity and sensitivity of tumor parenchyma ADC average have a high value. When presenting signs such as cystic degeneration, hemorrhage, supratentorial ventriculomegaly, and peritumoral edema, combined with features such as the location and ADC value of the lesion, it is conducive to the differential diagnosis of the two. Declarations Clinical trial number not applicable. Human Ethics and Consent to Participate declarations not applicable. Clinical trial number not applicable. Author Contribution Z and Y wrote the main text of the manuscript, F provided clinical data for some cases in the manuscript, and X provided guidance for the design, writing, and submission of the manuscript Acknowledgements We thank Guanke Cai for help in CT and MRI scanning. Funding This study did not receive funding support Compliance with Ethical Standards Guarantor: The scientific guarantor of this publication is Xihong Hu. Conflict of Interest: The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article. Statistics and Biometry: No complex statistical methods were necessary for this paper. Informed Consent: Written informed consent was obtained from all subjects (patients) in this study. Ethical Approval: Institutional Review Board approval was obtained. Study subjects or cohorts overlap: None. Methodology Methodology: retrospective diagnostic or prognostic study performed at one institution References Louis DN, Perry A, Wesseling P et al (2021) The 2021 WHO Classification of Tumors of the Central Nervous System: a summary. Neurooncology 23:1231–1251 Cohen AR (2022) Brain Tumors in Children. N Engl J Med 386:1922–1931 McKean-Cowdin R, Razavi P, Barrington-Trimis J et al (2013) Trends in childhood brain tumor incidence, 1973–2009. J Neurooncol 115:153–160 Millard NE, De Braganca KC (2016) Medulloblastoma. 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Diagn Cytopathol 23:329–332 Phuttharak W, Wannasarnmetha M, Wara-Asawapati S, Yuthawong S (2021) Diffusion MRI in Evaluation of Pediatric Posterior Fossa Tumors. Asian Pac J Cancer Prevention: APJCP 22:1129–1136 Tables Table 1 to 4 are available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table1.doc Table2.doc Table3.doc Table4.doc Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 12 May, 2026 Reviews received at journal 29 Apr, 2026 Reviewers agreed at journal 12 Apr, 2026 Reviewers invited by journal 23 Mar, 2026 Editor assigned by journal 22 Mar, 2026 Submission checks completed at journal 16 Mar, 2026 First submitted to journal 10 Mar, 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. 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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-9079157","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":611059247,"identity":"2d76af58-f7dc-41d1-8a1b-3deb8d913dc2","order_by":0,"name":"Zhiming Yang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDUlEQVRIiWNgGAWjYLACxgYJBjYw6wADAz8z8+EHpGmRbGdLMyBCC4wF1GJwnkdBAp9qg+NnD7/8ucMimk+6/QLDhzOHEzcf5mEwYKixicap5UxemoXkGYncNpkzBYwzbhxO3HaY98ADhmNpuQ24tBzIMTMwbANqkchJYOb5ANLCl2DA2HAYt5bzb8wMEmFa/gC1bG7mMZDAq+VGjvGDg2At6QeYGYAO28BMQIvkjTdmjI0QWxgYe86kG884DAzkBDx+4TufY/zxZ1td7vwZ6Q8Yfhyzlu3vP3z4wYcaG5xaFA4wsEFjgcf8BwNDsyNYZQIO5SAg38DA/AHCZH8AJOrs8SgeBaNgFIyCEQoAu+5l7ylZ3bQAAAAASUVORK5CYII=","orcid":"","institution":"Children's Hospital of Fudan University","correspondingAuthor":true,"prefix":"","firstName":"Zhiming","middleName":"","lastName":"Yang","suffix":""},{"id":611059248,"identity":"604c23bc-906f-43be-b068-e40d5ac2a13a","order_by":1,"name":"Yali Yue","email":"","orcid":"","institution":"Children's Hospital of Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Yali","middleName":"","lastName":"Yue","suffix":""},{"id":611059249,"identity":"3314e4fe-b2c7-4508-9d93-3453509542cc","order_by":2,"name":"Feixiao Wu","email":"","orcid":"","institution":"Children's Hospital of Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Feixiao","middleName":"","lastName":"Wu","suffix":""},{"id":611059250,"identity":"bd04867d-a681-4abf-b867-449e690222b4","order_by":3,"name":"Xihong Hu","email":"","orcid":"","institution":"Children's Hospital of Fudan University","correspondingAuthor":false,"prefix":"","firstName":"Xihong","middleName":"","lastName":"Hu","suffix":""}],"badges":[],"createdAt":"2026-03-10 04:54:03","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9079157/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9079157/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105410975,"identity":"f069f4e3-6d28-473d-a115-6d3630aedec6","added_by":"auto","created_at":"2026-03-25 17:20:06","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":157367,"visible":true,"origin":"","legend":"\u003cp\u003e(a, b) Transverse and sagittal T1WI images show a mixed signal of a large mass in the right frontal and temporal lobe, with equal signal intensity in the parenchymal components and central cystic degeneration. (c) The tumor parenchyma on transverse T2WI shows isointensity. (d) DWI shows that the majority of the parenchyma is of isointensity mixed with a small amount of high signal and the mass with restricted diffusion. (e) After enhancement, the tumor appears as a wreath-like enhancement around the central cyst on transverse T1WI.\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/4f1d11348ff7e02b705c219e.jpg"},{"id":105565598,"identity":"99aab579-fea8-4f69-957d-b4b50a837f6e","added_by":"auto","created_at":"2026-03-27 12:53:41","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":158452,"visible":true,"origin":"","legend":"\u003cp\u003e(a, b) Transverse and sagittal T1WI images show a mass located in the vermis of the cerebellum, with a relatively uniform low signal intensity. (c) On transverse T2WI, the tumor showed relatively uniform high signal intensity. (d) DWI shows high signal intensity. (e) After enhancement, the tumor showed relatively uniform and significant enhancement.\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/65322f87547ee1fc8d008e37.jpg"},{"id":105570232,"identity":"b2d1dddb-d740-415d-a5bf-706c08b9746c","added_by":"auto","created_at":"2026-03-27 13:15:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":846748,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/33bb0355-20ef-42fe-bf31-173ce1179f5d.pdf"},{"id":105566129,"identity":"85c6208d-1be9-4a93-84e2-183fd8b2e1f5","added_by":"auto","created_at":"2026-03-27 12:55:24","extension":"doc","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":33280,"visible":true,"origin":"","legend":"","description":"","filename":"Table1.doc","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/83a68f0e2e844082a42d35ad.doc"},{"id":105410977,"identity":"d9101426-461f-4c1b-bdb3-47994740bf13","added_by":"auto","created_at":"2026-03-25 17:20:07","extension":"doc","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":49664,"visible":true,"origin":"","legend":"","description":"","filename":"Table2.doc","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/49be32cdb0381e55b1e84168.doc"},{"id":105410978,"identity":"671c828e-8304-4d50-81c1-7e1866009957","added_by":"auto","created_at":"2026-03-25 17:20:07","extension":"doc","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":29696,"visible":true,"origin":"","legend":"","description":"","filename":"Table3.doc","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/ed86382f4586124226c509e7.doc"},{"id":105410980,"identity":"f060f9e9-7a80-4321-9476-ac3bbea5caf4","added_by":"auto","created_at":"2026-03-25 17:20:07","extension":"doc","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":130048,"visible":true,"origin":"","legend":"","description":"","filename":"Table4.doc","url":"https://assets-eu.researchsquare.com/files/rs-9079157/v1/9ad30981da610dcd37d57c64.doc"}],"financialInterests":"No competing interests reported.","formattedTitle":"A Case-control Study of MRI Features in Pediatric Atypical Teratoid Rhabdoid Tumor and Medulloblastoma","fulltext":[{"header":"Introduction","content":"\u003cp\u003e According to the 2021 World Health Organization (WHO) classification of central nervous system (CNS) tumors, atypical teratoid rhabdoid tumor (AT/RT) and medulloblastoma (MB) are classified as embryonic tumors[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Embryonic tumors account for approximately 20% of childhood brain tumors, characterized histologically by dense small round blue cells with scant cytoplasm and varying degrees of differentiation[2; 3]. Medulloblastoma is the most common malignant pediatric brain tumor, representing over 60% of childhood embryonic tumors[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. The presence of small round blue cells in about two-thirds of AT/RT cases led to its misdiagnosis as MB[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. There are even reported cases where immunohistochemistry confirmed tumors containing both AT/RT and MB components, or where initial pathology was typical for MB but recurrence presented with extraneural metastasis and rhabdoid differentiation[6; 7].\u003c/p\u003e\u003cp\u003eHowever, AT/RT carries a significantly worse prognosis due to higher malignancy, faster growth, younger age at onset, and greater invasiveness[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Current multimodal treatment involving surgery, radiotherapy, and systemic/intrathecal chemotherapy can achieve long-term survival rates of 60\u0026ndash;80% for MB patients and improve the 2-year progression-free and overall survival rates for AT/RT patients to 53% and 70%, respectively[9; 10]. Therefore, accurate preoperative imaging diagnosis is crucial for guiding surgical strategy, planning adjuvant therapy, and improving prognosis. The purpose of this study is to explore the clinical and MRI features that help differentiate AT/RT and MB in pediatric patients, in order to develop appropriate treatment plans and improve patient outcomes.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cp\u003e\u003cb\u003ePatients\u003c/b\u003e This retrospective study was approved by our Institutional Ethics Review Committee, and informed consent was obtained from the parents or guardians of all patients. A total of 114 patients diagnosed with AT/RT or MB by surgical pathology between January 1, 2010, and June 30, 2023, were enrolled, including 32 AT/RT and 82 MB cases. Clinical data, treatment details (surgery, chemotherapy, radiotherapy), and survival follow-up information were comprehensively reviewed.\u003c/p\u003e \u003cp\u003e \u003cb\u003eMR examination protocol\u003c/b\u003e Some patients (over 3 years old) cooperated after reassurance. For 69 uncooperative children (under 3 years old: 24 AT/RT, 45 MB), 10% chloral hydrate (0.5 ml/kg) was administered orally or via enema, and imaging proceeded after sleep induction. MRI was performed using a Siemens Magnetom Avanto 1.5T scanner with a head matrix coil. Sequences included non-contrast scans, DWI, and post-contrast scans with the following parameters: slice thickness 5 mm, gap 7 mm, FOV 240 \u0026times; 240 mm. These included axial and sagittal FLASH T1WI (TR 1450 ms, TE 25 ms), axial TSE T2WI (TR 9000 ms, TE 92 ms), and DWI (TR 5000 ms, TE 65 ms). DWI used b-values of 0 and 1000 s/mm\u0026sup2; applied in three orthogonal directions. The contrast agent for enhanced scanning was gadolinium diethylenetriamine pentaacetate (Gd-DTPA) at 0.5 mmol/mL (0.1 mmol/kg). Post-injection, axial and sagittal FLASH T1WI scans were repeated using the same parameters as the pre-contrast scan. On DWI images, regions of interest (ROIs) were carefully placed to avoid areas of hemorrhage, necrosis, or cystic degeneration.\u003c/p\u003e \u003cp\u003e \u003cb\u003eImage Analysis and ADC Measurement\u003c/b\u003e All images were retrospectively and independently reviewed by two radiologists with over ten years of neuroimaging experience using a Picture Archiving and Communication System (PACS) (GE Healthcare Centricity RIS CE V2.0), blinded to pathological results. Consensus was reached on the following features: off-midline growth, tumor size, signal intensity, enhancement characteristics, supratentorial ventriculomegaly, hemorrhage, cystic degeneration, peritumoral edema, tumor boundary (clear/unclear), peritumoral tissue invasion, and metastasis/dissemination. Off-midline growth was defined as tumor origin outside the fourth ventricle or cerebellar vermis, with the tumor mass entirely located to one side. Peritumoral edema was graded as: none; Grade I (edema extent\u0026thinsp;\u0026lt;\u0026thinsp;10% of tumor area on the same slice); Grade II (10\u0026ndash;50%); Grade III (50\u0026ndash;100%); Grade IV (\u0026gt;\u0026thinsp;100%)[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. For ADC measurement, a lesion slice showing relatively homogeneous signal in the solid component was selected. A circular or oval ROI (area: 10\u0026ndash;40 mm\u0026sup2;) was manually drawn on the corresponding DWI image. Three ROIs were placed at different levels within the solid part of each tumor, and the mean value was recorded as the ADC for that case.\u003c/p\u003e \u003cp\u003e \u003cb\u003eStatistical analysis\u003c/b\u003e Data were analyzed using SPSS software (version 22.0). For continuous variables (ADC values - min, max, mean; age; tumor size), normality and homogeneity of variance were assessed using the Kolmogorov-Smirnov test and Levene's test, respectively. As these assumptions were not met, the Mann-Whitney U test was employed for group comparisons. The diagnostic performance of the mean ADC was evaluated using receiver operating characteristic (ROC) curve analysis, with the optimal cut-off value determined by the Youden index. Sensitivity and specificity were calculated. Categorical variables (e.g., tumor location, off-midline growth, hemorrhage) were compared using the Pearson Chi-square test. Continuous data are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD), and categorical data as counts (percentages). A two-sided \u003cem\u003eP\u003c/em\u003e value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eClinical Characteristics\u0026nbsp;\u003c/strong\u003eThe study included 114 children: 32 with AT/RT (20 males, 12 females; age range 4 months-13 years, mean 3.8 \u0026plusmn; 4.5 years) and 82 with MB (56 males, 26 females; age range 3 months-13 years, mean 5.6 \u0026plusmn; 3.9 years). No significant differences were found in age or gender distribution between the groups (\u003cem\u003eP\u003c/em\u003e = 0.417 and \u003cem\u003eP\u003c/em\u003e = 0.658, respectively). During follow-up, 5 AT/RT and 6 MB patients were lost. Among those with complete data, the mean overall survival was significantly shorter for AT/RT (29.3 \u0026plusmn; 12.2 months, range 1-85) compared to MB (70.5 \u0026plusmn; 14.8 months, range 1-112) (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.001). Mortality was higher in the AT/RT group (81.4%, 22/27) than in the MB group (35.5%, 27/76) (\u003cem\u003eP\u003c/em\u003e = 0.007). The post-operative recurrence/disease progression rate was significantly higher for AT/RT (85.1%, 23/27) than for MB (38.1%, 29/76) (\u003cem\u003eP\u003c/em\u003e = 0.014). The time from surgery to recurrence/dissemination was also significantly shorter for AT/RT (7.3 \u0026plusmn; 11.4 months, range 1-29) than for MB (20.6 \u0026plusmn; 17.7 months, range 4-56) (\u003cem\u003eP\u003c/em\u003e = 0.002) (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eImaging Features\u0026nbsp;\u003c/strong\u003eThe maximum tumor diameter ranged from 17-95 mm (mean 49.2 \u0026plusmn; 17.0 mm) for AT/RT and 10-76 mm (mean 44.2 \u0026plusmn; 11.1 mm) for MB, with no significant difference (\u003cem\u003eP\u003c/em\u003e = 0.073).\u003c/p\u003e\n\u003cp\u003eRegarding MRI signal intensity, both groups showed predominantly iso- to hypointense or mixed signals on T1WI (\u003cem\u003eP\u003c/em\u003e = 0.83). On T2WI, AT/RT signals were predominantly slightly hyperintense (13 cases) or mixed (13 cases), whereas MB signals were predominantly slightly hyperintense (59 cases) (\u003cem\u003eP\u003c/em\u003e = 0.044).\u003c/p\u003e\n\u003cp\u003eOff-midline growth was significantly more frequent in AT/RT (56.3%, 18/32) than in MB (17.1%, 14/82) (\u003cem\u003eP\u003c/em\u003e = 0.001). MB tumors had clearer boundaries than AT/RT tumors (69.5% vs. 37.5%,\u003cem\u003e\u0026nbsp;P\u003c/em\u003e = 0.007) and were associated with a higher incidence of supratentorial ventriculomegaly (97.6% vs. 46.9%, \u003cem\u003eP\u003c/em\u003e = 0.001). AT/RT tumors showed a higher prevalence of peritumoral edema (78.1% vs. 37.8%,\u003cem\u003e\u0026nbsp;P\u003c/em\u003e = 0.001), intratumoral hemorrhage (31.2% vs. 8.5%, \u003cem\u003eP\u003c/em\u003e = 0.024), cystic degeneration (75.0% vs. 37.8%, \u003cem\u003eP\u003c/em\u003e = 0.035), and metastasis/dissemination (56.3% vs. 28.0%, \u003cem\u003eP\u003c/em\u003e = 0.042). No significant difference was found in enhancement patterns between the groups (\u003cem\u003eP\u003c/em\u003e = 0.223) (Table 2).\u003c/p\u003e\n\u003cp\u003eCharacteristic MRI features of AT/RT included off-midline location, markedly heterogeneous or wreath-like enhancement, cystic/necrotic components, hemorrhage, and significant peritumoral edema (Figure 1). MB typically presented as a midline posterior fossa mass causing supratentorial ventriculomegaly (Figure 2).\u003c/p\u003e\n\u003cp\u003eADC values derived from the solid tumor components showed statistically significant differences between groups for mean ADC, ADCmin, and ADCmax (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.001 for all). The mean ADC value was significantly lower in the AT/RT group (0.521 \u0026plusmn; 0.104 \u0026times; 10⁻\u0026sup3; mm\u0026sup2;/s, range 0.424-0.698) compared to the MB group (0.710 \u0026plusmn; 0.094 \u0026times; 10⁻\u0026sup3; mm\u0026sup2;/s, range 0.492-0.956) (Table 3). ROC curve analysis for mean ADC yielded an area under the curve (AUC) of 0.927. The optimal diagnostic cut-off was 0.622 \u0026times; 10⁻\u0026sup3; mm\u0026sup2;/s, providing a sensitivity of 90.1% and specificity of 87.5% for differentiating AT/RT from MB (Table 4).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eAT/RT and MB are both classified as WHO CNS grade 4 tumors[1]. AT/RT is a rare, highly aggressive malignant CNS tumor, typically affecting infants and young children under 3 years of age, accounting for 1.6% of CNS tumors in individuals \u0026le;19 years and 10.1% in those under 1 year[12; 13; 11; 14; 15]. Previous studies reported a younger onset age and possible male predominance for AT/RT compared to MB[11; 16]. However, our study found no significant differences in age or gender distribution, noting a recent trend of older female patients (\u0026gt;10 years) within the AT/RT group, suggesting evolving demographic patterns that warrant further investigation.\u003c/p\u003e\n\u003cp\u003eAT/RT is associated with a notably poor prognosis, as reflected in our findings: patients with AT/RT had significantly shorter overall survival, higher mortality and recurrence rates, and a shorter interval from surgery to tumor progression or dissemination compared to those with MB. The current study demonstrates that while maximum safe resection combined with early radiotherapy is a reasonable multi-mode treatment that can prolong the progression-free survival of AT/RT patients, only the degree of resection and adjuvant treatment status have a significant impact on overall survival and event-free survival[17], consequently the purpose of surgery should be to achieve complete resection. In the context of radiogenomics providing opportunities for risk stratification and selection of suitable targeted genetic analysis for MB, there has been the research being conducted by using MRI based machine to learn decision paths allowing for identification of four clinically relevant molecular subgroups of pediatric MB, the accuracy of tumor volume size measurement has also made progress[18; 19]. Therefore, considering the high malignancy of AT/RT, the similarity of the two tumor manifestations, and the differences in treatment, it is essential to differentiate AT/RT and MB.\u003c/p\u003e\n\u003cp\u003eIn this study, the incidence of AT/RT non midline growth was 61.9%, with lesions mostly located in the cerebellopontine angle, cerebellar hemisphere, and frontotemporal lobe. Multiple studies have indicated that AT/RT often grows in the cerebellopontine angle, with a higher incidence than other areas[20; 21; 16]. MB is characterized by the growth in the subtentorial midline, with an incidence of only 17.5% of off-midline growth, the difference between the two tumor groups in this study having attained statistical significance. The lesions of MB are mostly located in the fourth ventricle, cerebellar vermis, and other areas, resulting in compression and obstruction of the fourth ventricle, as well as hydrocephalic dilation of the third and lateral ventricles. Therefore, the statistical significance of difference in the incidence of supratentorial ventriculomegaly between the two groups may be related to this.\u0026nbsp;Compared to AT/RT, the lesions of MB are mostly solid or predominantly solid, with relatively infrequent cystic degeneration, necrosis, and hemorrhage[22-24]. In this study, the cystic degeneration rate of different degrees in the AT/RT group was 76.2%, significantly higher than that of the MB group at 37.5%. Hemorrhage is also a significant feature of AT/RT. Previous studies\u0026nbsp;have shown that AT/RT has a higher cerebral blood volume (CBV) value than MB[25], indicating that there is more abundant neovascularization in AT/RT, and the trend to intratumoral hemorrhage of AT/RT may be related to this characteristic. Due to its high malignancy, AT/RT is prone to spreading intracranial along the cerebrospinal fluid to the spinal cord, lateral ventricles, and even brainstem meninges, many studies have reported[22; 24; 26]. In this study, the metastasis and/or dissemination rate of AT/RT was 59.3% (19% in MB). It also showed that MB lesions have clearer boundaries than AT/RT lesions. There is a significant difference in peritumoral edema between the two groups. Peritumoral edema was more frequent and severe in AT/RT, with 57% of cases exhibiting grade II or higher edema, compared to only 22.5% in MB. Perhaps in addition to cytotoxic edema, ischemic edema caused by compression of the tumor and hydrocephalic dilation, the degree of peritumoral edema is also related to the high malignancy of AT/RT, corresponding with previous studies[22; 24; 14]. Although there was no significant difference in the enhancement patterns between the two groups, the AT/RT tumors were mainly mixed solid-cystic, with eccentric large cystic degeneration and annular enhancement of the parenchymal components，of which wreath-like enhancement had previously been shown as a relatively characteristic imaging feature in AT/RT[24]. This type of enhancement appeared in 5 of our cases in the AT/RT group, but not in the MB group.\u003c/p\u003e\n\u003cp\u003eA significant contribution of our study is the quantitative analysis of DWI. The mean ADC value of the solid tumor component was significantly lower in AT/RT (0.521 \u0026plusmn; 0.104 \u0026times; 10⁻\u0026sup3; mm\u0026sup2;/s) than in MB (0.710 \u0026plusmn; 0.094 \u0026times; 10⁻\u0026sup3; mm\u0026sup2;/s), with an optimal diagnostic cut-off of 0.622 \u0026times; 10⁻\u0026sup3; mm\u0026sup2;/s (AUC=0.927, sensitivity 90.1%, specificity 87.5%). This finding corroborates and extends previous reports[20; 27]. While earlier studies with smaller samples reported overlapping or variable ADC values, our larger cohort provides robust evidence that restricted diffusion is more pronounced in AT/RT. This lower ADC likely reflects higher cellular density and/or nuclear-to-cytoplasmic ratio within AT/RT, correlating with its higher histological grade and aggressive behavior. Notably, Wu et al also found significantly lower ADCmin and ADC ratios in AT/RT compared to MB, and highlighted a higher DWI ratio.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThis study has several limitations, including its retrospective design, the small cohort of AT/RT patients due to the rarity of the disease, and the absence of advanced MRI techniques such as perfusion imaging and MR spectroscopy. Furthermore, although certain imaging findings showed statistical significance, their diagnostic sensitivity and specificity may not yet be sufficient to replace surgical intervention and pathological confirmation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn summary, by combining clinical data to analyze MRI features and DWI parameters, this study can provide relatively reliable information for the differential diagnosis of intracranial AT/RT and MB in children. The specificity and sensitivity of tumor parenchyma ADC\u003csub\u003eaverage\u003c/sub\u003e have a high value. When presenting signs such as cystic degeneration, hemorrhage, supratentorial ventriculomegaly, and peritumoral edema, combined with features such as the location and ADC value of the lesion, it is conducive to the differential diagnosis of the two.\u003c/p\u003e"},{"header":"Declarations","content":" \u003ch2\u003eClinical trial number\u003c/h2\u003e \u003cp\u003enot applicable.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eHuman Ethics and Consent to Participate declarations\u003c/strong\u003e \u003cp\u003enot applicable.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eClinical trial number\u003c/strong\u003e \u003cp\u003enot applicable.\u003c/p\u003e \u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eZ and Y wrote the main text of the manuscript, F provided clinical data for some cases in the manuscript, and X provided guidance for the design, writing, and submission of the manuscript\u003c/p\u003e\u003cp\u003e\u003cstrong\u003e\u003cem\u003eAcknowledgements\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank Guanke Cai \u0026nbsp;for help in CT and MRI scanning.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eFunding\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study did not receive funding support\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eCompliance with Ethical Standards\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eGuarantor:\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe scientific guarantor of this publication is Xihong Hu.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eConflict of Interest:\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe \u0026nbsp;authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eStatistics and Biometry:\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo complex statistical methods were necessary for this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eInformed Consent:\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from all subjects (patients) in this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eEthical Approval:\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInstitutional Review Board approval was obtained.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eStudy subjects or cohorts overlap:\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eMethodology\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMethodology:\u0026nbsp; retrospective\u003c/p\u003e\n\u003cp\u003ediagnostic or prognostic study\u003c/p\u003e\n\u003cp\u003eperformed at one institution\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLouis DN, Perry A, Wesseling P et al (2021) The 2021 WHO Classification of Tumors of the Central Nervous System: a summary. Neurooncology 23:1231\u0026ndash;1251\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCohen AR (2022) Brain Tumors in Children. N Engl J Med 386:1922\u0026ndash;1931\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMcKean-Cowdin R, Razavi P, Barrington-Trimis J et al (2013) Trends in childhood brain tumor incidence, 1973\u0026ndash;2009. J Neurooncol 115:153\u0026ndash;160\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMillard NE, De Braganca KC (2016) Medulloblastoma. J Child Neurol 31:1341\u0026ndash;1353\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLi BK, Al-Karmi S, Huang A, Bouffet E (2020) Pediatric embryonal brain tumors in the molecular era. Expert Rev Mol Diagn 20:293\u0026ndash;303\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMiyata K, Hori T, Yamakawa K et al (2016) Medulloblastoma with epithelioid features in the cerebellar vermis. Pediatr Int 58:908\u0026ndash;912\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDonner LR (2005) Differentiation of classic medulloblastoma into metastatic large cell medulloblastoma with focal rhabdoid differentiation in the absence of posterior fossa recurrence. Acta Neuropathol 109:543\u0026ndash;551\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCasaos J, Huq S, Lott T et al (2018) Ribavirin as a potential therapeutic for atypical teratoid/rhabdoid tumors. Oncotarget 9:8054\u0026ndash;8067\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRamaswamy V, Remke M, Bouffet E et al (2016) Risk stratification of childhood medulloblastoma in the molecular era: the current consensus. Acta Neuropathol 131:821\u0026ndash;831\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChi SN, Zimmerman MA, Yao X et al (2009) Intensive multimodality treatment for children with newly diagnosed CNS atypical teratoid rhabdoid tumor. 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J Pediatr Neurosciences 6:90\u0026ndash;91\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMeyers SP, Khademian ZP, Biegel JA, Chuang SH, Korones DN, Zimmerman RA (2006) Primary intracranial atypical teratoid/rhabdoid tumors of infancy and childhood: MRI features and patient outcomes. AJNR Am J Neuroradiol 27:962\u0026ndash;971\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBambakidis NC, Robinson S, Cohen M, Cohen AR (2002) Atypical teratoid/rhabdoid tumors of the central nervous system: clinical, radiographic and pathologic features. Pediatr NeuroSurg 37:64\u0026ndash;70\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRorke LB, Packer RJ, Biegel JA (1996) Central nervous system atypical teratoid/rhabdoid tumors of infancy and childhood: definition of an entity. 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Cancer Med 12:10449\u0026ndash;10461\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFujita M, Sato M, Nakamura M et al (2005) Multicentric atypical teratoid/rhabdoid tumors occurring in the eye and fourth ventricle of an infant: case report. J Neurosurg 102:299\u0026ndash;302\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJin B, Feng XY (2013) MRI features of atypical teratoid/rhabdoid tumors in children. Pediatr Radiol 43:1001\u0026ndash;1008\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKoral K, Gargan L, Bowers DC et al (2008) Imaging characteristics of atypical teratoid-rhabdoid tumor in children compared with medulloblastoma. AJR Am J Roentgenol 190:809\u0026ndash;814\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParmar H, Hawkins C, Bouffet E, Rutka J, Shroff M (2006) Imaging findings in primary intracranial atypical teratoid/rhabdoid tumors. Pediatr Radiol 36:126\u0026ndash;132\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGoo HW, Ra Y (2017) Advanced MRI for Pediatric Brain Tumors with Emphasis on Clinical Benefits. Korean J Radiol 18:194\u0026ndash;207\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLu L, Wilkinson EJ, Yachnis AT (2000) CSF cytology of atypical teratoid/rhabdoid tumor of the brain in a two-year-old girl: a case report. Diagn Cytopathol 23:329\u0026ndash;332\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePhuttharak W, Wannasarnmetha M, Wara-Asawapati S, Yuthawong S (2021) Diffusion MRI in Evaluation of Pediatric Posterior Fossa Tumors. Asian Pac J Cancer Prevention: APJCP 22:1129\u0026ndash;1136\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 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":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"childs-nervous-system","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cnsy","sideBox":"Learn more about [Child's Nervous System](http://link.springer.com/journal/381)","snPcode":"381","submissionUrl":"https://submission.nature.com/new-submission/381/3","title":"Child's Nervous System","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Atypical teratoid rhabdoid tumor (AT/RT), Brain tumor, Magnetic resonance imaging, Medulloblastoma (MB)","lastPublishedDoi":"10.21203/rs.3.rs-9079157/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9079157/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eCompared to medulloblastoma (MB), atypical teratoid rhabdoid tumor (AT/RT) is characterized by a lower incidence, younger age at onset, and a poorer prognosis. Preoperative clinical and neuroimaging differentiation between these tumors remains challenging. This study aimed to evaluate the diagnostic utility of conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in distinguishing AT/RT from MB in children.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe retrospectively included 32 patients with AT/RT and 82 patients with MB confirmed by surgery and pathology in our hospital between 2010 and 2023. We analyzed the clinical data, preoperative MRI characteristics, and apparent diffusion coefficient (ADC) values of these patients to evaluate their diagnostic value.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe overall survival time of AT/RT patients was significantly shorter than that of MB patients (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.001), with a higher mortality rate (81.4% vs. 35.5%, \u003cem\u003eP\u003c/em\u003e = 0.007). Significant differences were found between AT/RT and MB in T2WI signal, off-midline growth, supratentorial ventriculomegaly, cystic degeneration, hemorrhage, peritumoral edema, tumor boundary clarity, and metastasis/dissemination (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05). No significant differences were observed in gender, age, lesion size, T1WI signal, or enhancement pattern (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05). The mean ADC value differed significantly between the two groups (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.001), with an optimal cut-off value of 0.622 × 10⁻³ mm²/s.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMRI features, including more cystic degeneration, hemorrhage, supratentorial ventriculomegaly, and peritumoral edema, combined with a lower ADC value may provide reliable information to differentiate AT/RT from MB in children.\u0026nbsp;\u003c/p\u003e","manuscriptTitle":"A Case-control Study of MRI Features in Pediatric Atypical Teratoid Rhabdoid Tumor and Medulloblastoma","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-25 17:20:02","doi":"10.21203/rs.3.rs-9079157/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-12T16:25:30+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-29T21:49:16+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"161451070573202112533822815507653712870","date":"2026-04-12T07:14:42+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-24T03:32:27+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-22T09:50:21+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-16T04:48:57+00:00","index":"","fulltext":""},{"type":"submitted","content":"Child's Nervous System","date":"2026-03-10T04:48:40+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"childs-nervous-system","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"cnsy","sideBox":"Learn more about [Child's Nervous System](http://link.springer.com/journal/381)","snPcode":"381","submissionUrl":"https://submission.nature.com/new-submission/381/3","title":"Child's Nervous System","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"3a0af124-1a35-46e9-ac4f-8f38cf78bf5b","owner":[],"postedDate":"March 25th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-12T16:25:30+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-29T21:49:16+00:00","index":19,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-18T15:08:20+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-25 17:20:02","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9079157","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9079157","identity":"rs-9079157","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}