Breastfeeding After Breast Cancer Safe
Breastfeeding after receiving treatment for breast cancer is safe, and women who have a germline BRCA mutation do not face an increased risk of recurrence or developing new breast cancers, according to data presented last month at the European Society for Medical Oncology (ESMO) 2024 Congress.1,2
“I hope these new findings will improve the way we counsel these patients,” Eva Blondeaux, MD, an oncologist with IRCCS Ospedale Policlinico San Martino in Genoa, Italy, who discussed the results of the second study involving women, said in a press release. The international study followed nearly 5000 young women carrying a germline BRCA mutation who had survived breast cancer.
Nearly 1 in 4 of the 474 women who subsequently gave birth breastfed their baby and just about half were unable to breastfeed because they had had both breasts removed to reduce their future cancer risk. After a median follow-up of 7 years from giving birth, there was no difference in the number of breast cancer recurrences or new breast cancers in women who breastfed their baby compared with those who did not breastfeed. There was also no difference in disease-free survival or overall survival.
A second study that expands the investigation beyond BRCA, addressing women with hormone receptor–positive early breast cancer, showed similar results, with no risks associated with breastfeeding.
The international POSITIVE study included 518 women who temporarily interrupted their breast cancer treatment to have a baby; 317 had at least 1 live birth and 64% of them breastfed. At 2 years from the first live birth, the proportion of women with breast cancer recurrence or new breast cancer was similar in those who breastfed (3.6%) as in those who did not breastfeed (3.1%).2
Commenting on the results in the release, Maria Alice Franzoi, MD, medical oncologist and researcher at Gustave Roussy, Villejuif, France, who was not involved in the study, said: “There was previously a lack of high-quality data regarding the feasibility and safety of breastfeeding in young women who have been treated for breast cancer. Until now, women and healthcare providers lacked information on whether breastfeeding is feasible after breast cancer surgery, on the safety of pausing adjuvant treatments for breastfeeding and on the hormonal changes related to it.”3 However, she cautioned that follow-up of the studies should, ideally, continue for longer.
“Data from these 2 studies will be extremely useful to guide our practical discussions with young women diagnosed with breast cancer,” Franzoi continued. “We should start thinking and discussing about survivorship care planning – including fertility preservation, pregnancy and breastfeeding for women who want to consider these options – at the time of diagnosis, so that they are prepared and empowered across the entire breast cancer journey for shared decision making,” she concluded.
References
- Blondeaux E, Delucchi V, Mariamidze E, et al. Breastfeeding after breast cancer in young BRCA carriers: results from an international cohort study. September 13-17, 2024. ESMO Congress 2024. Barcelona, Spain, & online; abstract 18150.
- Azim HA, Niman S, Partridge AH, et al. Breastfeeding in women with hormone receptor-positive breast cancer who conceived after temporary interruption of endocrine therapy: results from the POSITIVE trial. September 13-17, 2024. ESMO Congress 2024. Barcelona, Spain, & online; abstract 18140.
- ESMO. Studies provide first evidence that breastfeeding after breast cancer is safe. Press release. September 9, 2024. Accessed September 24, 2024. www.esmo.org/newsroom/press-and-media-hub/esmo-media-releases/studies-provide-first-evidence-that-breastfeeding-after-breast-cancer-is-safe