Survival Benefit of Temozolomide as Treatment for Glioblastoma; a Population Based Analysis
Mitchell S Wachtel, Bradley B Miller. Texas Tech University Health Sciences Center, Lubbock, TX
Background: In 2005, the European Organisation for Research and Treatment of Cancer Brain Tumor and Radiotherapy Groups and the National Cancer Institute of Canada Clinical Trials Group reported improved survival after diagnosis of glioblastoma multiforme when temozolomide was administered with radiotherapy versus treatment by radiotherapy alone. Hypothesized was the notion that a large database might identify improved survival in patients diagnosed with glioblastoma multiforme since publication of that study.
Design: A case listing session of the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute was performed to retrieve data concerning persons 40-70 years old at histologic diagnosis of glioblastoma multiforme for the periods 2003-2005 and 2006-2008 who had survived at least one month. Race, gender, age, and survival times were acquired. Two-year survival experiences were compared. Survival estimates were calculated by the Kaplan-Meier procedure. Log normal accelerated failure time regression estimated survival time ratios; the 2.5th and 97.5th percentiles of 3,000 bootstrap replicates were calculated to provision 95% confidence intervals. Age was transformed by a natural spline with five knots before entry into regression.
Results: The median age at diagnosis for the 7,720 patients was 58 years (interquartile range 52-64 years). 6960 (90.2%) were White, 412 (5.3%) were Black, and 348 (4.5%) were of unknown/other race. 3,030 (39.2%) were women; 4,690 (60.8%) were men. The figure displays survival curves. Adjusted for age, gender, and race, survival times for 2006-2008 were 11.4% (95% confidence interval 5.7-17.5%) longer than for 2003-2005.
Conclusions: Patients diagnosed after 2005 lived longer. Benefits of temozolomide in the treatment of glioblastoma multiforme are supported by analysis of the general patient population.
Tuesday, March 20, 2012 1:00 PM
Poster Session IV # 254, Tuesday Afternoon