LAUSR

Background Knowledge is growing on the safety of assisted reproductive techniques (ART) in cancer survivors. No data exist, however, for the specific population of breast cancer patients harboring germline BRCA1/2 pathogenic variants. Patients and methods This is a multicenter retrospective cohort study across 30 centers worldwide including women diagnosed at ≤40 years with stage I-III breast cancer, between January 2000 and December 2012, harboring known germline BRCA1/2 pathogenic variants. Patients included in this analysis had a post-treatment pregnancy either achieved through use of ART (ART group) or naturally (non-ART group). ART procedures included ovulation induction, ovarian stimulation for in vitro fertilization or intracytoplasmic sperm injection, and embryo transfer under hormonal replacement therapy. Results Among the 1424 patients registered in the study, 168 were eligible for inclusion in the present analysis, of whom 22 were in the ART group and 146 in the non-ART group. Survivors in the ART group conceived at an older age compared with those in the non-ART group (median age: 39.7 versus 35.4 years, respectively). Women in the ART group experienced more delivery complications compared with those in the non-ART group (22.1% versus 4.1%, respectively). No other apparent differences in obstetrical outcomes were observed between cohorts. The median follow-up from pregnancy was 3.4 years (range: 0.8-8.6 years) in the ART group and 5.0 years (range: 0.8-17.6 years) in the non-ART group. Two patients (9.1%) in the ART group experienced a disease-free survival event (specifically, a locoregional recurrence) compared with 40 patients (27.4%) in the non-ART group. In the ART group, no patients deceased compared with 10 patients (6.9%) in the non-ART group. Conclusion This study provides encouraging safety data on the use of ART in breast cancer survivors harboring germline pathogenic variants in BRCA1/2, when natural conception fails or when they opt for ART in order to carry out preimplantation genetic testing.