Racial Disparities in Overall Survival in Patients With Glioblastoma Before and After 2010
Abstract
Introduction and Objective. Glioblastomas are the most common and fatal malignancy of the brain. Despite scientific advances in cancer treatment, therapy options have remained relatively unchanged. In 2009, the FDA approved bevacizumab for the treatment of glioblastoma. Even with bevacizumab, the median survival length remained at a median of 12-14 months. While most studies suggest Asian Pacific Islanders (API) have a greater survival rate, it has not been determined if the introduction of bevacizumab modified the association between race and survival. Methods. Data from 22,276 patients were obtained from the Surveillance, Epidemiology, and End Results Program (SEER) during 1975 and 2018. Patients with death of unknown cause, unknown survival times, missing information regarding race/ethnicity or coded as other specified and recurrent glioblastoma were excluded. The exposure variable was race, the outcome variable was 3-year survival, and the effect modifier was diagnosis year. Unadjusted and adjusted Cox regression analysis were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). Results. The sample was 91.4% white and exhibited significant differences in diagnostic year, age at diagnosis, tumor size, and ethnicity but no significant differences in sex and surgical status. Blacks and API had greater cause specific survival than white patients in the adjusted model (blacks adjusted HR: 0.85 (95% CI 0.79-0.92), API adjusted HR: 0.90 (95% CI 0.83-0.98)). The HR was lower for diagnosis on or after 2010 compared to diagnosis before 2010 (adjusted HR: 0.71 (95% CI 0.69-0.74)). Conclusions-Implications. Our study found that diagnosis year does not act as an effect modifier. While previous studies found that API patients had the lowest hazard ratio, our study found that blacks had the lowest. Further research should clarify survival rates between races and provide biological/social explanations for these disparities.
Keywords
Glioblastoma, survival, death, race, bevacizumab
Presentation Type
Oral Presentation
Racial Disparities in Overall Survival in Patients With Glioblastoma Before and After 2010
Introduction and Objective. Glioblastomas are the most common and fatal malignancy of the brain. Despite scientific advances in cancer treatment, therapy options have remained relatively unchanged. In 2009, the FDA approved bevacizumab for the treatment of glioblastoma. Even with bevacizumab, the median survival length remained at a median of 12-14 months. While most studies suggest Asian Pacific Islanders (API) have a greater survival rate, it has not been determined if the introduction of bevacizumab modified the association between race and survival. Methods. Data from 22,276 patients were obtained from the Surveillance, Epidemiology, and End Results Program (SEER) during 1975 and 2018. Patients with death of unknown cause, unknown survival times, missing information regarding race/ethnicity or coded as other specified and recurrent glioblastoma were excluded. The exposure variable was race, the outcome variable was 3-year survival, and the effect modifier was diagnosis year. Unadjusted and adjusted Cox regression analysis were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). Results. The sample was 91.4% white and exhibited significant differences in diagnostic year, age at diagnosis, tumor size, and ethnicity but no significant differences in sex and surgical status. Blacks and API had greater cause specific survival than white patients in the adjusted model (blacks adjusted HR: 0.85 (95% CI 0.79-0.92), API adjusted HR: 0.90 (95% CI 0.83-0.98)). The HR was lower for diagnosis on or after 2010 compared to diagnosis before 2010 (adjusted HR: 0.71 (95% CI 0.69-0.74)). Conclusions-Implications. Our study found that diagnosis year does not act as an effect modifier. While previous studies found that API patients had the lowest hazard ratio, our study found that blacks had the lowest. Further research should clarify survival rates between races and provide biological/social explanations for these disparities.