Safety of pregnancy after breast cancer in young women with hormone receptor-positive disease: a systematic review and meta-analysis

Assessing risks and knowledge gaps on the impact of systemic therapies in early breast cancer on female fertility: A systematic review of the literature

The therapeutic landscape for early breast cancer (eBC) has expanded by introducing novel anticancer agents into clinical practice. During their reproductive years, women with eBC should be informed of the potential risk of premature ovarian insufficiency (POI) and infertility with the proposed systemic therapy. Although the topic of female fertility is becoming increasingly relevant in patients with cancer, limited information is available on the gonadotoxicity of new agents available for eBC treatment. Analyses from clinical trials and prospective data on ovarian function biomarkers are lacking. The purpose of this systematic review is to report the available preclinical and clinical data on female fertility risk with the use of the new agents that are part of clinical practice use or under development for eBC management. This review highlights the clear need to perform additional research efforts to improve our understanding on the gonoadtoxicity of new anticancer agents.

Is controlled ovarian stimulation safe in patients with hormone receptor-positive breast cancer receiving neoadjuvant chemotherapy?

INTRODUCTION

Controlled ovarian stimulation (COS) for oocyte/embryo cryopreservation is the method of choice for fertility preservation (FP) in young patients diagnosed with early-stage breast cancer (eBC). Nevertheless, some challenges still question its role, particularly in the neoadjuvant setting, where concerns arise about potential delay in the onset of anticancer treatment, and in hormone receptor-positive (HR+) disease, as cancer cells may proliferate under the estrogenic peak associated with stimulation. Therefore, this review aims to examine the available evidence on the safety of COS in eBC patients eligible for neoadjuvant treatment (NAT), particularly in HR+ disease.

METHODS

A comprehensive literature search was conducted to identify studies evaluating the feasibility and safety of COS in eBC and including patients referred to NAT and/or with HR+ disease. Time to NAT and survival outcomes were assessed.

RESULTS

Of the three matched cohort studies assessing the impact of COS on time to start NAT, only one reported a significant small delay in the cohort undergoing COS compared with the control group, whereas the other studies found no difference. Regarding survival outcomes, overall, no increased risk of recurrence or death was found, either in patients undergoing COS in the neoadjuvant setting regardless of HR expression or in HR+ disease regardless of the timing of COS relative to surgery. However, there are no data on the safety of COS in the specific combined scenario of HR+ disease undergoing NAT.

CONCLUSION

Neither the indication to NAT nor the HR positivity constitutes per se an a priori contraindication to COS. Shared decision making between clinicians and patients is essential to carefully weigh the risks and benefits in each individual case. Prospective studies designed to specifically investigate this issue are warranted.

Pregnancy After Breast Cancer in Young BRCA Carriers: An International Hospital-Based Cohort Study

Importance

Young women with breast cancer who have germline pathogenic variants in BRCA1 or BRCA2 face unique challenges regarding fertility. Previous studies demonstrating the feasibility and safety of pregnancy in breast cancer survivors included limited data regarding BRCA carriers.

Objective

To investigate cumulative incidence of pregnancy and disease-free survival in young women who are BRCA carriers.

Design, Setting, and Participants

International, multicenter, hospital-based, retrospective cohort study conducted at 78 participating centers worldwide. The study included female participants diagnosed with invasive breast cancer at age 40 years or younger between January 2000 and December 2020 carrying germline pathogenic variants in BRCA1 and/or BRCA2. Last delivery was October 7, 2022; last follow-up was February 20, 2023.

Exposure

Pregnancy after breast cancer.

Main Outcomes and Measures

Primary end points were cumulative incidence of pregnancy after breast cancer and disease-free survival. Secondary end points were breast cancer-specific survival, overall survival, pregnancy, and fetal and obstetric outcomes.

Results

Of 4732 BRCA carriers included, 659 had at least 1 pregnancy after breast cancer and 4073 did not. Median age at diagnosis in the overall cohort was 35 years (IQR, 31-38 years). Cumulative incidence of pregnancy at 10 years was 22% (95% CI, 21%-24%), with a median time from breast cancer diagnosis to conception of 3.5 years (IQR, 2.2-5.3 years). Among the 659 patients who had a pregnancy, 45 (6.9%) and 63 (9.7%) had an induced abortion or a miscarriage, respectively. Of the 517 patients (79.7%) with a completed pregnancy, 406 (91.0%) delivered at term (≥37 weeks) and 54 (10.4%) had twins. Among the 470 infants born with known information on pregnancy complications, 4 (0.9%) had documented congenital anomalies. Median follow-up was 7.8 years (IQR, 4.5-12.6 years). No significant difference in disease-free survival was observed between patients with or without a pregnancy after breast cancer (adjusted hazard ratio, 0.99; 95% CI, 0.81-1.20). Patients who had a pregnancy had significantly better breast cancer-specific survival and overall survival.

Conclusions and Relevance

In this global study, 1 in 5 young BRCA carriers conceived within 10 years after breast cancer diagnosis. Pregnancy following breast cancer in BRCA carriers was not associated with decreased disease-free survival.

Trial Registration

ClinicalTrials.gov Identifier: NCT03673306.