Adjuvant Treatment of Grade 4 Glioma, Outcomes at a UK Tertiary Center

Abstract

Aim: The 5-year overall survival (OS) for Glioblastoma (GBM) remains low. The cohort had a lower percentage of completing adjuvant treatment than those reported in trials. Therefore unplanned 6 cycles of adjuvant treatment and the effect on survival outcomes were assessed. Survival data for patients with Gliadel wafer insertion at the time of primary surgery was also assessed. The combination of these factors on survival outcomes was also assessed. Methods: The retrospective cohort study of 110 patients who underwent neurosurgery followed by chemoradiotherapy (CRT) 60 Gray in 30 fractions and adjuvant Temozolomide (TMZ) was carried out from 2007 to 2016. Overall survival (OS) and progression-free survival (PFS) were assessed and a number of subset analyses were carried out. Results: The period of OS was 16 months and PFS was 11.9 months. 57% of patients completed 4-6 cycles of adjuvant TMZ 43% received 3 or fewer cycles of TMZ. Those unable to complete planned adjuvant TMZ had a poorer OS (10 vs 20 months, Cox analysis P-value 0.0003). For patients having maximal safe debulking plus Gliadel wafer insertion, median OS was improved, 19.5 months P=0.06. In the group with the combination of significant factors, the median OS was 2 months greater than those that did not receive Gliadel wafers and could not complete 4 cycles of adjuvant TMZ. Conclusion: Survival outcomes were improved with Gliadel wafer insertion and completing 4-6 cycles of TMZ. Consequently, the combination of these factors led to improved outcomes.