P03.25 Impact of PCR based molecular analysis in daily diagnosis for the patient with gliomas

Introduction: WHO2016 CNS update requires combined histological-molecular classification. Previously, we assessed major IDH mutation and oligo-like character with immunohistochemistry. However, it is not enough to integrated diagnosis. Here, we present the sensitive, simple and cheap techniques for assessment of molecular information in daily diagnosis. Objectives and methods: Total 82 patients with gliomas assessed. Included patients are 36 glioblastomas, an anaplastic astrocytoma, 12 anaplastic oligodendrogliomas, 3 oligoastrocytomas, 11 anaplastic oligoastrocytomas, 7 oligodendrogliomas, 5 pilocytic astrocytomas and 7 pontine gliomas. Pathological diagnosis was performed with several staining including IDH1R132H, NKX2.2 and olig2. For assessment of 1p/19q LOH, FISH and PCR based microsatellite analysis (MS) were performed. For assessment of IDH, BRAF, H3F3A mutation, direct sequencing and qPCR using high resolution melting (HRM) were performed Results 1. For assessment of 1p/19q LOH codeletion, FISH using commercially available Vysis probe had a risk of high false positive rate compared with MS analysis. High immunopositivity against Olig2 and NKX2.2 correlated with 19q partial deletion. 2. For assessment of point mutations such as IDH, BRAFV600E, H3F3A, HRM is highly sensitive and low-cost technique compared with direct sequencing, Conclusion PCR based molecular analysis is a simple and an accurate technique in daily diagnosis, which is available for small lab.