Breast cancer surgical delays in a racially and ethnically diverse California cancer registry cohort.

Abstract

e12589 Background: Surgical delays for invasive breast cancer have been increasing over time and are associated with an increased risk of mortality. Black and Hispanic breast cancer patients are more likely to experience surgical delays than white patients; however, surgical delays among Asian ethnic subgroups remain unstudied. Methods: We used data from the population-based California Cancer Registry to identify all females diagnosed with stage I-III invasive breast cancer from 2012-2017. Our main independent variable was patient race/ethnicity, including five Asian ethnic subgroups. Covariates captured tumor, treatment-related, and patient sociodemographic characteristics. We conducted multivariable logistic regression to determine the odds of receiving surgery within 30 and 90 days of diagnosis and multivariable Cox proportional hazards regression to determine the risk of shorter time to surgical treatment. Results: Of 106,441 breast cancer patients, 57.5% were non-Hispanic white (NHW), 20.7% were Hispanic, 5.9% were non-Hispanic black (NHB), and 12.6% were Asian (consisting of 33.7% Filipino, 24.6% Chinese, 8.1% Asian Indian or Pakistani (AIP), 7.7% Japanese, 6.7% Korean, and 19.2% other Asian (OA) patients). Compared to NHWs, Hispanics and NHBs were less likely to receive surgical treatment within 30 and 90 days of diagnosis (Hispanic, 30-day: OR = 0.94, 95% CI = 0.89-0.98; Hispanic, 90-day: 0.89, 0.85-0.92; NHB, 30-day: 0.91, 0.85-0.98; NHB, 90-day: 0.86, 0.80-0.92). However, Chinese and AIP patients were more likely than NHWs to receive surgery within 30 and 90 days of diagnosis (Chinese, 30 day: OR = 1.30, 95% CI = 1.19-1.41; Chinese 90-day: 1.26, 1.08-1.47; AIP 30-day: 1.29, 1.11-1.50; AIP 90-day: 1.34, 1.17-1.53). In addition, Koreans were more likely than NHWs to receive surgery within 90 days of diagnosis (OR = 1.26, 95% CI = 1.08-1.47). Hispanics, NHBs, and OAs were less likely to receive timely treatment compared to NHWs (Hispanic: HR = 0.95, 95% CI = 0.94-0.97; NHB: 0.91, 0.89-0.94; OA: 0.95, 0.92-0.99), while Chinese, AIP, and Korean patients were more likely to receive timely treatment compared to NHWs (Chinese: HR = 1.15, 95% CI = 1.11-1.20; AIP: 1.10, 1.04-1.17; Korean: 1.10, 1.03-1.17). Lastly, patients diagnosed in 2017 were 14% less likely to receive timely treatment than those diagnosed in 2012 (HR: 0.86, 95% CI = 0.84-0.88). Conclusions: In this population-based cohort of female breast cancer patients in California, Hispanics and NHBs continue to experience surgical treatment delays and Asian American minority subgroups experience similar delays compared to NHWs. In addition, increasing delays over time could potentially exacerbate racial/ethnic disparities in breast cancer mortality. Continued work investigating the causes of breast cancer treatment delays among Asian ethnic subgroups is necessary to fully elucidate and target racial/ethnic treatment disparities.