Molecular profiling of different glioma specimens from an Ollier disease patient suggests a multifocal disease process in the setting of IDH mosaicism

AbstractOllier disease (OD) and Maffucci syndrome are rare conditions due to a post-zygotic somatic mutation that results in mosaicism. In addition to enchondromas and hemangiomas, some of these patients also develop other unrelated tumors, such as gliomas, that harborIDH mutations, suggesting that anIDH mutation is a common genetic event in the tumorigenesis in this group of patients. We illustrate an interesting case of multifocalIDH-mutant astrocytomas in an OD patient with 8  years of follow-up. We first demonstrated identicalIDH mutations in the brain tumor samples from various locations in this patient, but different1p,19q results by fluorescent in-situ hybridization, different whole genome copy number profiles by OncoScan analysis, and a discrepantIDH2M131I mutation unique to one tumor, supporting a multifocal disease process in the setting of somaticIDH mosaicism.

Source: Brain Tumor Pathology - October 1, 2018 Category: Neurology Source Type: research