title: Findings from frozen sections of spinal subependymomas: Is it possible to differentiate this diagnosis from other common spinal tumors?
abstract: Subependymomas are slow-growing, benign neoplasms that are rarely found in the spinal cord. Because of the differences in the treatment plans, it might be very helpful for neurosurgeons to intraoperatively establish a diagnosis of spinal subependymoma, differentiated from other spinal intramedullary tumors. In this study, we analyzed frozen sections of spinal subependymomas to identify potential histological clues of spinal subependymomas to differentiate them from tumors that mimic spinal subependymoma. We reviewed the frozen sections and the corresponding permanent slides for 7 cases of spinal subependymoma. The spinal subependymomas showed several characteristic patterns, including, most importantly, an eccentric or both central and eccentric location in the axial plane. Histologically, they showed a (1) well-demarcated and multinodular mass with (2) low or moderate cellularity, (3) a microlobular pattern, and (4) small clusters of neoplastic cells. These features appear to be very specific to spinal subependymomas and could help differentiate them from ependymomas or astrocytomas. Although we might not be able to provide an exact diagnosis of all spinal subependymomas using these histological features, we hope that they help neuropathologists and neurosurgeons to adequately diagnose and treat spinal subependymomas.
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Korea.|Department of Pathology, Dankook University College of Medicine, Cheonan, Korea.
authors.forename: Seung Kyu
authors.initials: SK
authors.lastname: Choi
authors.affiliation: Department of Neurosurgery, National Health Insurance Service Ilsan Hospital, Ilsan, Korea.|Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Byeongwoo
authors.initials: B
authors.lastname: Kim
authors.affiliation: Department of Neurology, Hallym University, Gangnam Sacred Heart Hospital, Seoul, Korea.
authors.forename: Yang Ki
authors.initials: YK
authors.lastname: Minn
authors.affiliation: Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Keung-Nyun
authors.initials: KN
authors.lastname: Kim
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Korea. paxco@yuhs.ac.
authors.forename: Se Hoon
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D005629:Frozen Sections; D018315:Glioma, Subependymal / Q000175:diagnosis* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013120:Spinal Cord Neoplasms / Q000175:diagnosis* / Q000473:pathology*
keywords: Frozen section; Histology; Spinal cord; Subependymoma