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

Outcome of Patients with Pregnancy-Associated Breast Cancer Who Have Subsequent Pregnancies

BACKGROUND

After treatment of pregnancy-associated breast cancer (PABC), some women desire future pregnancy. While safety of pregnancy after breast cancer has been demonstrated, the same cannot be said about women with PABC.

OBJECTIVE

The aim of this study was to describe the incidence and outcomes of patients with PABC with subsequent pregnancies compared with those without another pregnancy.

METHODS

A retrospective chart review identified patients diagnosed with breast cancer during pregnancy or within 5 years postpartum between 2011 and 2023. Patients were then screened for further pregnancy. Clinicopathologic variables, oncologic outcomes, and pregnancy outcomes were recorded. The Chi-square test and t-test were used to compare patients with subsequent pregnancy with those without. Kaplan-Meier method and log-rank test were used to estimate 5-year disease-free survival (DFS).

RESULTS

Overall, 75 patients with PABC were identified, 58 of whom had PABC and no further pregnancies (NSP-PABC) and 17 with subsequent pregnancy (SP-PABC). Compared with patients with NSP-PABC, patients with SP-PABC were significantly younger (p = 0.015) and less likely to have prior pregnancies (p < 0.001). Overall median follow-up was 4.3 years. Calculated 5-year DFS rates were 86.2% and 89.0% for the SP-PABC and NSP-PABC groups, respectively (p = 0.76). Calculated 5-year overall survival was 100% and 90.7% for the SP-PABC and NSP-PABC groups, respectively (p = 0.22). Within the SP-PABC group, 14/17 patients had successful deliveries.

CONCLUSIONS

This study provides the first descriptions of patients with PABC and subsequent pregnancy. Additional investigation, likely with pooled analysis from multiple institutions, is necessary to determine the oncologic and obstetric safety of pregnancy following PABC.

Current practices in oncofertility counseling: updated evidence on fertility preservation and post-treatment pregnancies in young women affected by early breast cancer

INTRODUCTION

Anticancer treatments have significantly contributed to increasing cure rates of breast cancer in the last years; however, they can also lead to short- and long-term side effects, including gonadotoxicity, and compromised fertility in young women. Oncofertility is a crucial issue for young patients who have not yet completed their family planning at the time of cancer diagnosis.

AREAS COVERED

This review aims to cover all the latest available evidence in the field of oncofertility, including the gonadotoxicity of currently adopted anticancer therapies in the curative breast cancer setting, the available strategies for fertility preservation and the feasibility of achieving a pregnancy following anticancer treatment completion.

EXPERT OPINION

Over the past years, a significant progress has been made in oncofertility care for young women with breast cancer. In the context of the currently available evidence, every young woman with newly diagnosed breast cancer should receive a proper and complete oncofertility counseling before starting any anticancer treatment to increase her chances of future pregnancies.

Impact of Hormone Receptor Status and Tumor Subtypes of Breast Cancer in Young BRCA Carriers

BACKGROUND

Hormone receptor expression is a known positive prognostic and predictive factor in breast cancer; however, limited evidence exists on its impact on prognosis of young patients harboring BRCA pathogenic variant (PV).

PATIENTS AND METHODS

This international, multicenter, retrospective cohort study included young patients (≤40 years) diagnosed with invasive breast cancer and harboring germline PV in BRCA genes. We investigated the impact of hormone receptor status on clinical behavior and outcomes of breast cancer. Outcomes of interest (disease-free survival [DFS], breast cancer specific survival [BCSS] and overall survival [OS]) were first investigated according to hormone receptors expression (positive vs. negative), and then according to breast cancer subtype (luminal A-like vs. luminal B-like vs. triple-negative vs. HER2-positive breast cancer).

RESULTS

From 78 centers worldwide, 4,709 BRCA carriers were included, of whom 2,143 (45.5%) had hormone receptor-positive and 2,566 (54.5%) hormone receptor-negative breast cancer. Median follow-up was 7.9 years. The rate of distant recurrences was higher in patients with hormone receptor-positive disease (13.1% vs. 9.6%, p<0.001), while the rate of second primary breast cancer was lower (9.1% vs. 14.7%, p<0.001) compared to patients with hormone receptor-negative disease. The 8-years DFS was 65.8% and 63.4% in patients with hormone receptor-positive and negative disease, respectively. The hazard ratio of hormone receptor-positive vs. negative disease changed over time for DFS, BCSS, and OS (p<0.05 for interactions of hormone receptor status and survival time). Patients with luminal A-like breast cancer had the worst long-term prognosis in terms of DFS compared to all the other subgroups (8-years DFS: 60.8% in luminal A-like vs. 63.5% in triple-negative vs. 65.5% in HER2-positive and 69.7% in luminal B-like subtype).

CONCLUSIONS

In young BRCA carriers, differences in recurrence pattern and second primary breast cancer among hormone receptor-positive vs. negative disease warrants consideration in counseling patients on treatment, follow-up, and risk-reducing surgery.

Fertility and Pregnancy-Related Issues in Young BRCA Carriers With Breast Cancer

Approximately 10% to 15% of breast cancer cases in young women are diagnosed in patients harbouring germline (g) pathogenic or likely pathogenic variants (PVs) in the BReast CAncer 1 (BRCA1) or BReast CAncer 2 (BRCA2) genes. Preclinical and clinical studies showed a potential negative effect of germline BRCA1/2 (gBRCA1/2) PVs on ovarian reserve and reproductive potential, even before starting anticancer therapies. The aim of this article is to summarize the current literature on the fertility potential of young gBRCA1/2 PVs carriers with breast cancer and the risk of gonadotoxicity associated with anticancer treatments. Moreover, we describe the available evidence on the efficacy of fertility preservation techniques in young gBRCA1/2 PVs carriers and the safety data on having a pregnancy after breast cancer treatment.

Fertility Preservation and Assisted Reproduction in Patients With Breast Cancer Interrupting Adjuvant Endocrine Therapy to Attempt Pregnancy

PURPOSE

We investigated time to pregnancy, efficacy and safety of fertility preservation, and assisted reproductive technologies (ARTs) in women with early hormone receptor-positive breast cancer (BC) desiring future pregnancy.

PATIENTS AND METHODS

POSITIVE is an international, single-arm, prospective trial, in which 518 women temporarily interrupted adjuvant endocrine therapy to attempt pregnancy. We evaluated menstruation recovery and factors associated with time to pregnancy and investigated if ART use was associated with achieving pregnancy. The cumulative incidence of BC-free interval (BCFI) events was estimated according to the use of ovarian stimulation at diagnosis. The median follow-up was 41 months.

RESULTS

Two hundred seventy-three patients (53%) reported amenorrhea at enrollment, of whom 94% resumed menses within 12 months. Among 497 patients evaluable for pregnancy, 368 (74%) reported at least one pregnancy. Young age was the main factor associated with shorter time to pregnancy with cumulative incidences of pregnancy by 1 year of 63.5%, 54.3%, and 37.7% for patients age <35, 35-39, and 40-42 years, respectively. One hundred and seventy-nine patients (36%) had embryo/oocyte cryopreservation at diagnosis, of whom 68 reported embryo transfer after enrollment. Cryopreserved embryo transfer was the only ART associated with higher chance of pregnancy (odds ratio, 2.41 [95% CI, 1.75 to 4.95]). The cumulative incidence of BCFI events at 3 years was similar for women who underwent ovarian stimulation for cryopreservation at diagnosis, 9.7% (95% CI, 6.0 to 15.4), compared with those who did not, 8.7% (95% CI, 6.0 to 12.5).

CONCLUSION

In POSITIVE, fertility preservation using ovarian stimulation was not associated with short-term detrimental impact on cancer prognosis. Pregnancy rates were highest among those who underwent embryo/oocyte cryopreservation followed by embryo transfer.

Fertility Preservation in BRCA1/2 Germline Mutation Carriers: An Overview

BRCA1 and BRCA2 mutations are responsible for a higher incidence of breast and ovarian cancer (from 55% up to 70% vs. 12% in the general population). If their functions have been widely investigated in the onset of these malignancies, still little is known about their role in fertility impairment. Cancer patients treated with antineoplastic drugs can be susceptible to their gonadotoxicity and, in women, some of them can induce apoptotic program in premature ovarian follicles, progressive depletion of ovarian reserve and, consequently, cancer treatment-related infertility (CTRI). BRCA variants seem to be associated with early infertility, thus accelerating treatment impairment of ovaries and making women face the concrete possibility of an early pregnancy. In this regard, fertility preservation (FP) procedures should be discussed in oncofertility counseling-from the first line of prevention with risk-reducing salpingo-oophorectomy (RRSO) to the new experimental ovarian stem cells (OSCs) model as a new way to obtain in vitro-differentiated oocytes, several techniques may represent a valid option to BRCA-mutated patients. In this review, we revisit knowledge about BRCA involvement in lower fertility, pregnancy feasibility, and the fertility preservation (FP) options available.

Fertility and reproductive concerns related to the new generation of cancer drugs and the clinical implication for young individuals undergoing treatments for solid tumors

The treatment landscape of solid tumors has changed markedly in the last years. Molecularly targeted treatments and immunotherapies have been implemented and have, in many cancers, lowered the risk of relapse and prolonged survival. Patients with tumors harboring specific targetable molecular alterations or mutations are often of a younger age, and hence future fertility and family building can be important concerns in this group. However, there are great uncertainties regarding the effect of the new drugs on reproductive functions, including fertility, pregnancy and lactation and how young patients with cancers, both women and men should be advised. The goal with this review is to gather the current knowledge regarding oncofertility and the different novel therapies, including immune checkpoint inhibitors, antibody-drug conjugates, small molecules and monoclonal antibody targeted therapies. The specific circumstances and reproductive concerns in different patient groups where novel treatments have been broadly introduced are also discussed, including those with melanoma, lung, breast, colorectal and gynecological cancers. It is clear, that more awareness is needed regarding potential drug toxicity on reproductive tissues, and it is of essence that individuals are informed based on current expertise and on available fertility preservation methods.

2023 Year in review: Early breast cancer

The results of several studies aiming to tailor early breast cancer treatment to individual risk were released in 2023. Axillary lymph node dissections and radiotherapy may be safely omitted in carefully selected patients. Sustained benefit from adjuvant CDK4/6 inhibitors was observed in high-risk hormone receptor-positive disease and the addition of immunotherapy to neoadjuvant chemotherapy improved pathological response. Continued benefit from perioperative pembrolizumab was reported in patients with triple negative breast cancer, while atezolizumab did not improve the risk of recurrence either pre- or postoperatively. The chance of pregnancy was higher in younger patients attempting to conceive after breast cancer.

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.