THE IMPACT OF MOLECULAR DIAGNOSTICS ON FUNCTION AND SYMPTOM BURDEN IN GLIOMA PATIENTS

IDH mutation status and 1p19q loss have been shown to be predictors of survival and are incorporated into the 2016 WHO diagnostic criteria. The impact of molecular subgroups on function and symptom outcomes have not been explored. A cross-sectional sample of ninety patients participating in the MDACC PROACTIVE study completed the M.D. Anderson Symptom Inventory-Brain Tumor. Functional status (KPS), demographic and clinical factors (disease grade, treatment status, recurrence, and surgery extent) were also collected. Group means and associations were compared with Mann-Whitney tests and chi-square tests. A two-way ANOVA evaluated the interaction of IDH status and performance on symptom burden. The sample was primarily male (65%) GBM (43%) patients, with a median age of 46 (range 20-84) with 41% having had a recurrence. Sixty-three percent of patients (n=44) were IDH wild type (IDHw), 42 IDH mutated (IDHm) with the majority of these also exhibiting TP53mutation (23%), and 13% with 1p19q loss. Two-thirds of patients with poor KPS had IDHw tumors. Patients with poor KPS reported worse overall (U=295.5,p<0.01), neurologic (U=241.0,p<0.01), and treatment-related (U=359.0,p<0.01) symptom burden and overall (U=174.0,p<0.01), activity-related (U=155.5,p<0.01), and mood-related (U=347.5,p<0.01)) interference scores. While symptom burden/interference did not differ based on molecular status, there was a significant interaction between IDH status and KPS, with patients with IDHm and poor KPS (n=8) reporting higher symptom burden (F(1,81)=7.21,p<0.01) compared to all other molecular subgroups. Patients with IDHw tumors were more likely to have lower KPS. Symptom burden did not differ based on IDH status, in itself. Rather, it was in conjunction with KPS that differences were seen in symptom severity, with patients with IDHm tumors with poor KPS experiencing the most severe symptom burden. This potentially is a consequence of IDHm tumor’s infiltrative nature. Future studies exploring associated imaging characteristics are warranted.