PATH-36. IDH AND TERT PROMOTER MUTATIONS IN NON-DIAGNOSTIC BIOPSIES FROM GLIOMA PATIENTS. (5th November 2018)

• Record Type: Journal Article
• Authors: Barritault, Marc; Picart, Thiebaud; Poncet, Delphine; Fenouil, Tanguy; Guyotat, Jacques; Jouanneau, Emmanuel; Joubert, Bastien; Vasiljevic, Alexandre; Honnorat, Jerôme; Meyronet, David; Ducray, Francois
• Is Part Of: Neuro-oncology. Volume 20(2018)Supplement 6
• Page Start: vi166
• Page End: vi166
• Publication Date: 2018-11-05
• Subjects: Brain Neoplasms -- Periodicals; Brain -- Tumors -- Periodicals; Brain -- Cancer -- Periodicals; Nervous system -- Cancer -- Periodicals; 616.99481
• DOI: 10.1093/neuonc/noy148.692
• Languages: English
• ISSNs: 1522-8517

Abstract

Abstract: BACKGROUND: Non-diagnostic biopsies are a recurrent issue in patients with a suspected brain tumor. Herein, in order to explore the utility of molecular testing in this setting, we determined whether IDH and TERT promoter (pTERT) mutations can be detected in non-diagnostic biopsies from glioma patients. METHODS: Using Snapshot PCR, we retrospectively assessed IDH and pTERT mutation status in 28 adult glioma patients in whom a first non-diagnostic biopsy had led to perform a second biopsy. RESULTS: Median age at diagnosis was 65 years and median delay between the first and second biopsy 21 days. The first biopsy consisted of not characterizable infiltrated glial cells (n=19), hemorrhage (n=4), necrosis (n=2) or normal tissue (n=3). The second biopsy demonstrated an IDH-wildtype glioblastoma (n=22), an IDH-wildtype astrocytoma (n=4), an IDH-mutant oligodendroglioma (n=1) and an IDH-mutant astrocytoma (n=1). A pTERT mutation was present in 21 cases. Retrospectively, the same IDH and pTERT mutations were identified in the non-diagnostic biopsies of the 2 patients with an IDH-mutant glioma and of 12 out of 21 patients with a pTERT-mutant glioma (57%). Overall an IDH and/or a pTERT mutation were detected in the non-diagnostic biopsies of 13 out of the 22 IDH-mutant and/or pTERT-mutant gliomas (59%) and in 13 out of the 28 cases included in the present series (46%). CONCLUSION: IDH and pTERT mutations can be detected in a high percentage of non-diagnostic biopsies from glioma patients supporting a role for molecular testing in the interpretation of non-diagnostic biopsies from patients with a suspected brain tumor.