Implication of telomere length as a proliferation-associated marker in schwannomas

Background and Objectives: Some schwannomas in the central nervous system may demonstrate relatively aggressive behavior in pathological findings and clinical course. We evaluate the diagnostic values of telomerase activity and telomere length in the clinicopathological behavior of schwannomas. Methods: Thirty surgical specimens from intracranial and intraspinal schwannomas were analyzed by polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) for telomerase activity and terminal restriction fragments (TRFs) using Southern blot for telomere length. Proliferative indices were also studied. Results: Telomerase activity could not be detected in all schwannomas. Elongated telomere length (mean 17,101 +/- 259 bp) was found in four specimens (13.3%). Three of these four were found to have mitotic figures, high vascularity, cellularity, and pleomorphism in the pathological findings. The proliferative indices (less than or equal to15) showed correlative high values. One patient died of this disease, and one was found to have recurrence at follow-up evaluation. Those that displayed benign histopathological pictures showed relatively short telomere length (8,866 +/- 271 base pairs) and low proliferative indices (less than or equal to1). These is a significant difference between these two groups (P = 0.001). Conclusions: Elongation of telomere length in schwannomas appears to predict aggressive clinicopathological behavior. (C) 2002 Wiley-Liss, Inc.