Temporal trends in Black-White disparities in cancer surgery and cancer-specific survival in the United States between 2007 and 2015

Background The American Society of Clinical Oncology (ASCO) has strived to address racial/ethnic disparities in cancer care since 2009. Surgery plays a pivotal role in cancer care; however, it is unclear whether and how racial/ethnic disparities in cancer surgery have changed over time. Methods This cohort study included 1,113,256 White and Black cancer patients across 9 years (2007-2015) using patient data extracted from the Surveillance, Epidemiology, and End Results (SEER)-18 registries. Patient data were included from 2007 to adjust insurance status and by 2015 to obtain at least a 3-year survival follow-up (until 2018). The primary outcome was a surgical intervention. The secondary outcomes were the use of (neo)adjuvant chemotherapy and cancer-specific survival (CSS). Adjusted associations of the race (Black/White) with the outcomes were measured in each cancer type and year. Results The gap between surgery rates for Black and White patients narrowed overall, from an adjusted odds ratio (aOR) of 0.621 (0.592-0.652) in 2007 to 0.734 (0.702-0.768) in 2015. However, the racial gap persisted in the surgery rates for lung, breast, prostate, esophageal, and ovarian cancers. In surgically treated patients with lymph node metastasis, Black patients with colorectal cancer (CRC) were less likely to receive (neo)adjuvant chemotherapy than White patients. Black patients undergoing surgery were more likely to have a worse CSS rate than White patients undergoing surgery. In breast cancer patients, the overall trend was narrow, but continuously present, with an adjusted hazard ratio (aHR) of 1.224 (1.278-1.173) in 2007 and 1.042 (1.132-0.96) in 2015. Conclusions Overall, progress has been made toward narrowing the Black-White gap in cancer surgical opportunity and survival. Future efforts should be directed toward those specific cancers for which the Black-White gap continues. Additionally, it is worth addressing the Black-White gap regarding the use of (neo)adjuvant chemotherapy for CRC treatment.