Key clinical point: Compared with good or low adherence to adjuvant hormone therapy (HT), excellent adherence was associated with a significantly reduced risk for subsequent breast tumors (SBT) in older women with ductal carcinoma in situ (DCIS) of the breast.
Major finding: In patients with excellent vs low adherence to adjuvant HT, both breast-conserving surgery (BCS) and BCS + radiation therapy (RT) significantly reduced the risks for SBT (−10.54 and −6.24 percentage points, respectively; both P < .00001) or subsequent invasive breast cancer (−8.85 and −4.28 percentage points, respectively; both P < .00001). Similar results were obtained in patients with excellent vs good adherence to adjuvant HT.
Study details: Findings are from an analysis of a population-based study including 3075 women with DCIS who were age ≥ 65 years and underwent BCS either with (75%) or without RT (25%).
Disclosures: This study was supported by the US National Cancer Institute. Two authors declared serving as consultants for various sources.
Source: Mitchell JM et al. Adherence to hormonal therapy after surgery among older women with ductal carcinoma in situ: Implications for breast cancer-related adverse health events. Cancer. 2023 (Sep 26). Doi: 10.1002/cncr.35009
