INNV-12. A SINGLE-INSTITUTION RETROSPECTIVE REVIEW OF PATIENTS WITH CNS TUMORS WHO INITIATED A KETOGENIC DIET

Abstract

Abstract BACKGROUND Many patients with CNS tumors express interest in initiating a ketogenic diet (KD). Following a discussion with the physician regarding the limited clinical evidence of KD for CNS tumors, interested patients were referred for evaluation by an oncology-certified dietitian. METHODS We performed a single institution retrospective chart review of patients with CNS tumors on a KD. Demographics, clinical characteristics, and diet information were extracted from patient charts. Descriptive statistics were conducted to summarize patterns of adherence to KD across patient characteristics. RESULTS From May 2016 to May 2018, 40 patients expressed interest in KD; 24 initiated it. M:F = 18:6, median age 46 (range 27–62). Diagnoses: 18 glioblastoma, 1 anaplastic astrocytoma, 2 grade 2 astrocytoma, 1 grade 2 oligodendroglioma, 1 spinal grade 2 astrocytoma, 1 chordoma. 18 tumors with methylated MGMT, 8 with mutant IDH1. At diet initiation, median KPS 80 (range 70–100); median BMI 25.6 (20.8–39). Median days on diet = 190 days; interquartile range 126–673 days; range 24–1479 days. Diet composition: 15 patients on 3:1 diet (grams fat: grams protein + carbs), 7 patients on 2:1, 2 patients on 1:1. 14 patients monitored blood ketone levels. 11 patients stopped KD: 5 for restrictiveness of diet (median 158 days, range 60–239); 1 for decreased KPS (673 days); 1 for excessive weight loss (108 days); 2 for disease progression (24 and 217 days); 2 lost to follow-up (109 and 125 days). In this small sample, no statistically significant associations between time on diet and age / gender / BMI / KPS / diet composition. However, trend toward longer adherence to diet in females, age < 50, 2:1 diet. CONCLUSION It is feasible for patients with CNS tumors to adopt KD. Results from prospective studies are needed to assess effects on QOL, neurocognition, performance status, and survival.