Ann Surg 2020 Dec 23;Publish Ahead of Print. Epub 2020 Dec 23.
Department of Surgery, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, South Korea Dana-Farber Cancer Institute, Boston, MA, USA Brigham and Women's Hospital, Boston, MA, USA Mayo Clinic, Rochester, MN, USA Stanford University, Palo Alto, CA, USA Beth Israel Deaconess Medical Center, Boston, MA, USA Massachusetts General Hospital, Boston, MA, USA University of Colorado Cancer Center, Aurora, CO, USA Sunnybrook Health Sciences Centre, Toronto, Ontario, USA Metrowest Medical Center, Framingham, MA, USA.
Objective: We aimed to investigate eligibility for breast-conserving surgery (BCS) pre- and post-neoadjuvant systemic therapy (NST), and trends in the surgical treatment of young breast cancer patients.
Background: Young women with breast cancer are more likely to present with larger tumors and aggressive phenotypes, and may benefit from NST. Little is known about how response to NAC influences surgical decisions in young women.
Methods: The Young Women's Breast Cancer Study (YWS), a multicenter prospective cohort of women diagnosed with breast cancer at age ≤40, enrolled 1302 patients from 2006 to 2016. Disease characteristics, surgical recommendations, and reasons for choosing mastectomy among BCS-eligible patients were obtained through the medical record. Trends in use of NST, rate of clinical and pathologic complete response (cCR and pCR), and surgery were also assessed.
Results: Of 1117 women with unilateral stage I-III breast cancer, 315 (28%) received NST. Pre-NST, 26% were BCS eligible, 17% were borderline eligible, and 55% were ineligible. After NST, BCS eligibility increased from 26% to 42% (p < 0.0001). Among BCS-eligible patients after NST (n = 133), 41% chose mastectomy with reasons being patient preference (53%), BRCA or TP53 mutation (35%) and family history (5%). From 2006 to 2016, the rates of NST (p = 0.0012), cCR (p < 0.0001) and bilateral mastectomy (p < 0.0001) increased, but the rate of BCS did not increase (p = 0.34).
Conclusion: While the proportion of young women eligible for BCS increased after NST, many patients choose mastectomy, suggesting that surgical decisions are often driven by factors beyond extent of disease and treatment response.