Temporal treatment trends for ductal carcinoma In situ by race and ethnicity in the United States.

BACKGROUND: Ductal carcinoma in situ (DCIS) accounts for approximately 15% of breast neoplasms, with breast-conserving surgery (BCS) with radiation considered standard of care. Recent treatment trends and racial and ethnic differences remain unexamined. METHODS: Retrospective cohort study of 292,260 women with DCIS (2006-2021) using Surveillance, Epidemiology, and End Results Program. Local treatment and reconstruction rates were evaluated overall and by race and ethnicity using Joinpoint and logistic regression. RESULTS: BCS with radiation was the most common treatment representing 42%-46% across all racial and ethnic groups. Over time, BCS with radiation and unilateral mastectomy rates decreased, bilateral mastectomy increased, and BCS without radiation fluctuated. BCS with radiation rates across racial and ethnic groups decreased over time, with no statistically significant differences by 2017-2021. NH Asian/Pacific Islander women (OR = 1.63, 95%CI=1.53 to 1.74), NH Black (OR = 1.45, 95%CI=1.36 to 1.54), and Hispanic women (OR = 1.22, 95%CI=1.14 to 1.29) were more likely than NH White women to undergo unilateral mastectomy in 2017-2021. Across all years, NH White women were more likely to undergo bilateral mastectomy than women in other racial and ethnic groups. Reconstruction rates generally increased over time. NH White women had the highest reconstruction rates (19.2%), while NH Asian/Pacific Islander, NH Black, and Hispanic women remained significantly less likely to undergo reconstruction. CONCLUSIONS: BCS with radiation rates have converged across racial and ethnic groups, but unilateral mastectomy remained more common among NH Black, NH Asian/Pacific Islander, and Hispanic women, while NH White women were more likely to undergo bilateral mastectomy and reconstruction.