Race in ovarian cancer treatment and survival: a systematic review with meta-analysis

There has long been recognition of racial disparities in cancer treatment and survival. In order to investigate the etiology of racial disparities in ovarian cancer, we undertook a systematic review of the published literature. Focusing on North America, our search of MEDLINE, PsychInfo, and EMBASE databases recovered 513 abstracts of which 98 underwent full text screening resulting in 24 studies included in the final review. After assessing heterogeneity, results were pooled where possible in a meta-analysis using a random effects model. Eight articles reported treatment outcomes, nine survival, and seven both. Overall African Americans were less likely to receive any form of surgical treatment for ovarian cancer [pooled relative risk (RR) 1.17 (95% confidence interval (CI): 1.10, 1.23)] compared with white women. Although the majority of the included articles reporting survival outcomes did not control for known covariates such as medical co-morbidities or treatment, we were able to pool the unadjusted results from eight articles. Taken together the meta-analysis of 106,704 women did not find a difference in five-year survival between whites and African Americans, RR 1.07 (95% CI: 0.97, 1.18). When the results were stratified by year of cancer diagnosis, studies which captured patients prior to 1985 yielded a five-year RR of survival for whites compared to African Americans of 0.93 (95% CI: 0.89, 0.97) compared with 1.17 (95% CI: 1.05, 1.31) after 1985. These results suggest that racial disparities in ovarian cancer are not due to underlying biological differences rather to the unequal application of existing treatments.