Abstract PR009: Breast cancer (BC) risk reduction in young women with ductal carcinoma in situ (DCIS)
Authors: Tesch Megan E. , Wong Julia S. , Dominici Laura , Ruddy Kathryn J. , Tamini Rulla , Schapira Lidia , Borges Virginia F. , Warner Ellen , Come Steven E. , Sepucha Karen , Collins Laura C. , Partridge Ann H. , Rosenberg Shoshana M. 
Published: December 2022

Abstract
Background: Young women with DCIS are at increased risk of recurrence and second BC compared to older women and may derive the greatest benefit from risk reduction strategies. Little is known about treatment decision-making, engagement in preventive behaviors, or fear of recurrence among young DCIS survivors. Thus, we sought to investigate treatment and prevention issues in this population. Methods: Using a multicenter prospective cohort that enrolled 1302 women with stage 0-IV BC at age ≤40, we identified participants with DCIS only who completed surveys in the year following diagnosis (dx). Surveys assessed treatment decisions, lifestyle factors (alcohol, smoking, physical activity [PA]), and fear of recurrence (Lasry Scale). Data was summarized with descriptive statistics and groups were compared with Fisher’s exact test. Results: Among 87 patients (median age 38, range 26-40), 75 had available treatment decision data, 19 (25%) of whom had breast-conserving surgery (BCS), 11 (15%) unilateral mastectomy (UM), and 45 (60%) bilateral mastectomy (BM). Most (77%) indicated their doctor said BCS was an option or recommended, including 34 (59%) who had BM. Of 40 patients who reported a patient-driven surgical decision, 73% had BM, 13% UM, and 15% BCS. Among 15 patients who reported the decision as doctor-driven, none had BM, 27% UM, and 73% BCS. Those who had BM were more likely to be extremely confident about the decision (80% vs. 73% UM vs. 53% BCS, p=0.022). Adjuvant tamoxifen was used by 10/27 (37%) patients with ER+ DCIS who had BCS/UM. Most who took tamoxifen reported this decision was shared with their doctor (90%); 1 reported the decision was made on her own. Of the 17 patients who did not take tamoxifen, 88% indicated their doctor said endocrine therapy was an option or recommended. Among all 87 patients, 31 (36%) were former and 3 (4%) were current smokers at baseline assessment (median 5 months post-dx); 51 (59%) never smoked. Overall, 4 quit within 1 year of dx. Most patients (83%) were current drinkers at baseline, though 79% consumed &lt;5 alcoholic beverages/week; 8% reported lower consumption at 1 year. Regarding PA at 1 year, 73% (58/80) reported ≥150 minutes of moderate-intensity PA/week. Overall, 41% of young survivors were at least moderately concerned about their BC coming back, with concern varying numerically by surgery (65% post-BCS, 50% post-UM, 29% post-BM, p=0.053). Conclusions: BC recurrence concerns were frequent among young DCIS patients, particularly among those with remaining breast tissue. BM decisions were largely patient-driven and made with high confidence, reflecting preferences towards surgical prevention. While adherence to survivorship lifestyle guidelines was high, including not smoking, consumption of ≤7 drinks/week, and engaging in PA, tamoxifen use was low, even when offered by a provider. Young DCIS survivors appear motivated to lower future BC risk through surgery and maintenance of healthy behaviors, and less so with tamoxifen; such values should be considered during treatment and survivorship counseling.
Citation Format: Megan E. Tesch, Julia S. Wong, Laura Dominici, Kathryn J. Ruddy, Rulla Tamini, Lidia Schapira, Virginia F. Borges, Ellen Warner, Steven E. Come, Karen Sepucha, Laura C. Collins, Ann H. Partridge, Shoshana M. Rosenberg. Breast cancer (BC) risk reduction in young women with ductal carcinoma in situ (DCIS) [abstract]. In: Proceedings of the AACR Special Conference on Rethinking DCIS: An Opportunity for Prevention?; 2022 Sep 8-11; Philadelphia, PA. Philadelphia (PA): AACR; Can Prev Res 2022;15(12 Suppl_1): Abstract nr PR009.