Childbirth after perioperative systemic therapy in patients with breast cancer: a retrospective single institutional study in Japan

Background: The number of breast cancer patients of childbearing age has been increasing. Therefore, we investigated the characteristics and the childbearing status of the patients who received systemic therapy for breast cancer during their childbearing age to better understand the clinical impact of childbirth.

Methods: Female patients with breast cancer younger than 40 years old who underwent surgery and received perioperative systemic therapy from 2007 to 2014 were included in this study. We compared the characteristics of patients with and without childbirth after treatment.

Result: Of 590 patients, 26 delivered a child, and 355 did not bear a child during the median observation period of 8.1 years, whilst 209 had unknown childbirth data. The childbirth group had a lower mean age at surgery (32.2 vs. 35.1, P < 0.001). The proportion of patients who desired childbirth and used assisted reproductive technology was significantly higher in the childbirth group (65.4 vs. 23.9% and 45.2 vs. 5.1%, respectively, P < 0.001). The patients in the childbirth group had significantly less advanced disease (P = 0.002). In the childbirth group, the age at childbirth was significantly older in patients who received combined endocrine therapy and chemotherapy (40.8 years) than in patients who received either alone (endocrine therapy: 36.9 years, chemotherapy: 36.7 years, P = 0.04). However, survival was not different between those with and without childbirth.

Conclusion: It is critical to recognize the desire for childbirth in patients with breast cancer who are receiving systemic therapy and to provide them with necessary fertility information before treatment to support their decision-making.