Supratentorial extraventricular ependymomas (STEEs) are relatively rare ependymomas, and their pathologic and genetic characteristics are still poorly understood. The aim of this study was to determine the histologic, immunohistochemical, and RELA fusion features, as well as to clarify in more detail the clinical courses of STEEs. Data from a total of 43 patients with STEEs was analyzed retrospectively. The status of RELA fusion was evaluated using fluorescence in situ hybridization. The expression levels of L1CAM, p65, cyclin D1, and p53 were assessed using immunohistochemistry. Progression-free survival and overall survival were calculated via Kaplan-Meier estimation using the log-rank test. Among all 43 STEEs, 65.1% (28/43) are positive for RELA fusion. Interestingly, almost half of the patients with RELA fusion–positive ependymomas are adults (13/28), and 89.3% (25/28) cases are anaplastic ependymomas, which suggests that RELA fusion testing is necessary in adults with STEEs. We investigated the immunohistochemical status of p65, L1CAM and CCND1 protein expression for their ability to predict RELA fusion status. RELA fusion–positive STEEs are frequently associated with expression of p65 (85.2%), L1CAM (85.2%), and CCND1 (81.5%). The accuracy of predicting RELA fusion status was much higher when the expression of p65 and L1CAM was combined, that is, when both were immunopositive. The status of RELA fusion, p53 overexpression, and extent of tumor resection are significantly associated with prognosis.
Departments of *Pathology
∥Neurosurgery, Xuanwu Hospital Capital Medical University
†Department of Pathology, Beijing Fengtai Hospital
¶Department of Pathology, Peking University International Hospital, Beijing
‡Department of Pathology, Guangdong Sanjiu Brain Hospital
**Department of Pathology, Guangdong Provincial Peoples Hospital, Guangzhou
#Department of Pathology, Jining People’s Hospital, Jining, China
Supported by Beijing Excellent Talent Training Project Grant (201600026833ZK07), National Natural Science Foundation of China (81401040), and Beijing Higher Education Young Elite Teacher Project (CIT&TCD201904091) to L.W., and Natural Science Foundation of Guangdong (2017A030313779) to Z.L.
L.W., L.L., and H.L. analyzed the data. P.W. and Y.W. analyzed the imaging features and clinical data. M.Z., W.W., and Z.L. provided essential material. Z.H., L.L., and L.Z. performed the experiments. L.W. and D.L. reviewed the pathologic diagnosis. L.W. and L.T. wrote the draft of the manuscript. All authors approved the final version of the manuscript.
Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article.
Correspondence: Lianghong Teng, PhD, MD, Department of Pathology, Xuanwu Hospital Capital Medical University, No. 45, Changchun Street, Xicheng District, Beijing 100053, China (e-mail: email@example.com).
Online date: August 6, 2019