ATRX status correlates with 11  C-methionine uptake in WHO grade II and III gliomas with IDH1 mutations

This study was designed to determine whether ATRX status correlates with uptake of11C-methionine in WHO grades II and III gliomas. Sixty-two patients underwent11C-methionine positron emission tomography scans prior to histological diagnosis. The tumor-to-normal ratio (T/N) of11C-methionine uptake was calculated by dividing the maximum standardized uptake value (SUV) for the tumor by the mean SUV of the normal brain. After surgery, tumor samples were subjected to immunohistochemistry for ATRX and IDH1-R132H followed byIDH1/2 sequencing. Twenty-seven of the sixty-two patients were found to have theIDH mutation. Nine of the twenty-seven gliomas harboring IDH mutations exhibited loss of nuclear ATRX expression, which is accompanied with an astrocytic tumor lineage and a poor prognosis. The mean T/N ratio in tumors with loss of nuclear ATRX expression was 2.20  ± 0.53, i.e., significantly lower than that of tumors with ATRX retention (3.28 ± 1.32,p = 0.0171,U test). Our study showed ATRX status to correlate with the T/N ratio and the outcomes of WHO grade II and III glioma patients with the IDH1 mutation. Our data provide new information on the biology and imaging characteristics of gliomas.

Source: Brain Tumor Pathology - February 28, 2017 Category: Neurology Source Type: research