Breastfeeding after breast cancer in young BRCA carriers

Blondeaux, E; Kim, HJ; Delucchi, V; Mariamidze, E; Bernstein-Molho, R; Frank, S; Ferrari, A; Linn, S; Agostinetto, E; Paluch-Shimon, S; Cortesi, L; Di Meglio, A; Balmana, J; Yerushalmi, R; Rodriguez-Wallberg, KA; Renaud, T; Cui, W; Moore, HCF; Wong, SM; Pogoda, K; Lustberg, M; Phillips, KA; Han, S; Puglisi, F; Vernieri, C; Bajpai, J; Sonnenblick, A; Rousset-Jablonski, C; De Marchis, L; De Giorgi, U; Bianchini, G; Texeira, L; Duhoux, FP; Villarreal-Garza, C; Sini, V; Fruscio, R; Del Mastro, L; Demeestere, I; Azim, HA, Jr; Peccatori, FA; Partridge, AH; Lambertini, M

Author(s): Blondeaux, E; Kim, HJ; Delucchi, V; Mariamidze, E; Bernstein-Molho, R; Frank, S; Ferrari, A; Linn, S; Agostinetto, E; Paluch-Shimon, S; Cortesi, L; Di Meglio, A; Balmana, J; Yerushalmi, R; Rodriguez-Wallberg, KA; Renaud, T; Cui, W; Moore, HCF; Wong, SM; Pogoda, K; Lustberg, M; Phillips, KA; Han, S; Puglisi, F; Vernieri, C; Bajpai, J; Sonnenblick, A; Rousset-Jablonski, C; De Marchis, L; De Giorgi, U; Bianchini, G; Texeira, L; Duhoux, FP; Villarreal-Garza, C; Sini, V; Fruscio, R; Del Mastro, L; Demeestere, I; Azim, HA, Jr; Peccatori, FA; Partridge, AH; Lambertini, M;
Details: Publication Year 2025-11-01,Volume 117,Issue #11,Page 2229-2239
Journal Title: Journal of the National Cancer Institute
Publication Type: Research article
Abstract: BACKGROUND: We investigated safety of breastfeeding after breast cancer in patients carrying germline BRCA pathogenic or likely pathogenic variants. METHODS: This was an international, multicenter, hospital-based, retrospective cohort study including BRCA carriers diagnosed with stage I-III invasive breast cancer at age 40 years or younger between January 2000 and December 2020 (NCT03673306). Locoregional recurrences and/or contralateral breast cancers, disease-free survival (DFS), and overall survival (OS) were compared between patients who breastfed after delivery and those who did not. RESULTS: Among 4732 patients included from 78 centers worldwide, 659 had a pregnancy after breast cancer diagnosis, of whom 474 delivered a child. After excluding patients with uptake of bilateral risk-reducing mastectomy prior to delivery (n = 225) or unknown breastfeeding status (n = 71), 110 (61.8%) breastfed (median duration 5 months) and 68 (38.2%) did not breastfeed. Compared to patients in the no breastfeeding group, those who breastfed were more frequently nulliparous at breast cancer diagnosis (61.8% vs 45.6%) and did not report prior smoking habit (71.8% vs 57.4%). After a median follow-up of 7.0 years following delivery, 7-year cumulative incidence of locoregional recurrences and/or contralateral breast cancers was 29% in the breastfeeding group and 36% in the no breastfeeding group (adjusted subdistribution hazard ratio [HR] = 1.08, 95% CI = 0.57 to 2.06). No difference in DFS (adjusted hazard ratio [aHR] = 0.83, 95% CI = 0.49 to 1.41) nor in OS (aHR = 1.32, 95% CI = 0.31 to 5.66) was observed. CONCLUSIONS: Breastfeeding did not appear to be associated with a higher risk of developing locoregional recurrences or contralateral breast cancers, emphasizing the possibility of achieving a balance between maternal and infant needs without compromising oncological safety.
Publisher: Oxford University Press
Keywords: Humans; Female; *Breast Neoplasms/genetics/pathology/epidemiology/mortality; *Breast Feeding/statistics & numerical data; Adult; Retrospective Studies; *BRCA1 Protein/genetics; Germ-Line Mutation; *BRCA2 Protein/genetics; *Neoplasm Recurrence, Local/epidemiology/genetics; Heterozygote; Pregnancy; Disease-Free Survival
Department(s): Medical Oncology
Publisher's Version: https://doi.org/10.1093/jnci/djaf177
Open Access at Publisher's Site: https://doi.org/10.1093/jnci/djaf177
Terms of Use/Rights Notice: Refer to copyright notice on published article.

Creation Date: 2025-07-22 03:30:57

Last Modified: 2026-01-06 02:46:49