The impact of fertility preservation on the timing of breast cancer treatment, recurrence, and survival

Background Many young women with breast cancer undergo fertility preservation (FP) before cancer treatment. This study examined the impact of FP on breast cancer outcomes. Methods The authors performed a retrospective cohort study of 272 women aged 20 to 45 years with newly diagnosed stage 0 to III breast cancer who underwent an FP consultation between 2005 and 2017. Among these women, 123 (45.2%) underwent FP (fertility preservation–positive [FP+]). The remaining 149 women did not undergo FP (fertility preservation–negative [FP–]). Results The characteristics at enrollment were similar with the exception of ethnicity (FP+, 87.8% White; FP–, 67.8% White; P = .002) and BRCA status (FP+, 27.7% BRCA+; FP–, 15.5% BRCA+; P = .021). The median follow‐up was approximately 4 years. Women who underwent FP had longer times to first treatment (FP+, 37 days; FP–, 31 days; adjusted hazard ratio [aHR], 0.74; confidence interval [CI], 0.56‐0.99) and neoadjuvant chemotherapy (FP+, 36 days; FP–, 26 days; aHR, 0.41; CI, 0.24‐0.68) and from surgery to adjuvant chemotherapy (FP+, 41 days; FP–, 33 days; aHR, 0.58; CI, 0.38‐0.90). Adjusted 3‐ and 5‐year invasive disease–free survival (IDFS) rates were comparable between the 2 groups (3‐year IDFS: FP+, 85.4%; FP–, 79.4%; P = .411; 5‐year IDFS: FP+, 73.7%; FP–, 67.1%; P = .288). Similarly, no difference in overall survival (OS) was observed between the 2 groups (3‐year OS: FP+, 95.5%; FP–, 93.5%; P = .854; 5‐year OS: FP+, 84.2%; FP–, 81.4%; P = .700). Conclusions FP after a breast cancer diagnosis delays the time to treatment by a small amount, but this delay does not lead to inferior IDFS or OS. Controlled ovarian stimulation for the purpose of fertility preservation in patients with breast cancer delays the initiation of systemic treatment but does not affect recurrence or survival. Fertility preservation provides a safe option for women diagnosed with breast cancer who are facing gonadotoxic treatment regimens and desire future fertility.