Impact of BRCA mutations and hormone receptor status on reproductive potential in breast cancer patients undergoing fertility preservation

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.

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.

BRCA Mutations and Fertility Preservation

Hereditary cancers mostly affect the adolescent and young adult population (AYA) at reproductive age. Mutations in BReast CAncer (BRCA) genes are responsible for the majority of cases of hereditary breast and ovarian cancer. BRCA1 and BRCA2 act as tumor suppressor genes as they are key regulators of DNA repair through homologous recombination. Evidence of the accumulation of DNA double-strand break has been reported in aging oocytes, while BRCA expression decreases, leading to the hypothesis that BRCA mutation may impact fertility. Moreover, patients exposed to anticancer treatments are at higher risk of fertility-related issues, and BRCA mutations could exacerbate the treatment-induced depletion of the ovarian reserve. In this review, we summarized the functions of both genes and reported the current knowledge on the impact of BRCA mutations on ovarian ageing, premature ovarian insufficiency, female fertility preservation strategies and insights about male infertility. Altogether, this review provides relevant up-to-date information on the impact of BRCA1/2 mutations on fertility. Notably, BRCA-mutated patients should be adequately counselled for fertility preservation strategies, considering their higher sensitivity to chemotherapy gonadotoxic effects.

Controlled ovarian hyperstimulation in breast cancer patients: Does oestrogen receptor status make a difference?

BACKGROUND

The presence of different breast cancer receptor status may impact ovarian stimulation outcomes.

AIM

To study the association between oestrogen receptor (ER) status in breast cancer patients and fertility preservation outcomes in a major tertiary referral centre.

MATERIALS AND METHODS

Women who underwent fertility preservation following the diagnosis of breast cancer from 2008 to 2018 were included in the study. Patient age, ovarian stimulation parameters and laboratory outcomes were recorded and compared between the ER positive and negative groups. The primary outcome was total number of oocytes frozen. Secondary outcomes included total number of oocytes collected, mature oocytes, and embryos frozen.

RESULTS

The women included in the study (n = 214) were analysed in the following groups based on their fertility preservation method: oocyte freezing (n = 131), embryo freezing (n = 70), and both embryo and oocyte freezing (n = 13). There was an increase in the mean (but not mature) number of oocytes frozen (12.4 and 9.2, P-value = 0.03) favouring the ER positive group, even though the women in this group were older (35.0 and 33.4, P-value of 0.03). There is no difference in the starting follicle-stimulating hormone dose, duration of stimulation, mature oocytes collected, and embryos frozen in both groups.

CONCLUSION

Patients with ER positive breast cancer may have more positive ovarian stimulation outcomes.

Ovarian stimulation and oocyte cryopreservation in females with cancer

PURPOSE OF REVIEW

We reviewed the most recent developments including the safety and effectiveness data and success rates in individualized ovarian stimulation protocols for adult and postpubertal females with cancer.

RECENT FINDINGS

In women with breast cancer, aromatase inhibitor- and tamoxifen-supplemented stimulation protocols increase the margin of safety by limiting estrogen exposure. The outcomes of ovarian stimulation appear similar between cancer and noncancer populations, even with the recently developed random-start protocols, which allow initiation of ovarian stimulation anytime during the menstrual cycle. Based on lower anti-Mullerian hormone levels and primordial follicle density, carriers of BRCA pathogenic variants ( BRCApv ) have decreased ovarian reserve in comparison to women without those variants and may lose larger portion of their ovarian reserve post chemotherapy. Oocyte cryopreservation is also emerging as a suitable fertility preservation approach for selected postpubertal girls as young as 12 years of age.

SUMMARY

Individualized ovarian stimulation approaches combined with improvements in cryopreservation techniques increased the success and safety margin to preserve fertility with oocyte freezing. Women with BRCApv , on the other hand, may be at disadvantage as they have lower ovarian reserve and may lose larger portion of their ovarian reserve post chemotherapy compared to women who do not carry these variants.

Outcomes of Fertility Preservation for Female Cancer Patients in a Single Tertiary Center

PURPOSE

To report our experience of fertility preservation (FP) in female cancer patients.

MATERIALS AND METHODS

We retrospectively analyzed the medical records of female who underwent elective oocyte or embryo cryopreservation before cancer treatment between January 2015 and December 2020 at Asan Medical Center. We analyzed the type of cancer, the rate of reuse of cryopreserved oocytes or embryos, and fertility outcomes such as the resumption of menstruation or pregnancy.

RESULTS

A total of 174 patients underwent 182 oocyte retrieval cycles after controlled ovarian stimulation for oocyte or embryo cryopreservation. The median age of patients was 33.0 (range 19-46) years, and the patients were most unmarried female (65.52%). The majority of patients were diagnosed with breast cancer (78.16%), and the remaining were diagnosed with gastrointestinal (6.33%) and hematologic malignancies (5.75%). The maturation rate of oocyte cryopreservation was 83.33%, and the fertilization rate of embryo cryopreservation was 72.07%. Of the 57 patients currently not undergoing cancer treatment, 34 resumed menstruating and 19 (33.33%, 19/57) returned to attempt a pregnancy. Among them, five patients succeeded in natural pregnancy. Eleven patients received frozen-thawed embryo transfer, and four patients succeeded in becoming pregnant (36.36%, 4/11). Only 6.3% of patients returned to use their gametes, and 93.7% of gametes are still in storage.

CONCLUSION

FP in cancer patients should be considered before cancer treatment. Through continuous research on oncofertility, it is necessary to consider how to increase the return rate and provide appropriate information to cancer patients of reproductive age.

Fertility Preservation in Young Women With Breast Cancer: A Review

Fertility preservation is a major concern in young patients diagnosed with breast cancer and planning to receive multimodality treatment, including gonadotoxic chemotherapy with or without age-related decline through long-term endocrine therapy. Most breast cancer patients undergo multimodality treatments; many short-term and long-term side effects arise during these therapies. One of the most detrimental side effects is reduced fertility due to gonadotoxic treatments with resultant psychosocial stress. Cryopreservation of oocytes, embryos, and ovarian tissue are currently available fertility preservation methods for these patients. As an adjunct to these methods, in vitro maturation or gonadotropin-releasing hormone agonist could also be considered. It is also essential to communicate well with patients in the decision-making process on fertility preservation. It is essential to refer patients diagnosed with breast cancer on time to fertility specialists for individualized treatment, which may lead to desirable outcomes. To do so, a multimodal team-based approach and in-depth discussion on the treatment of breast cancer and fertility preservation is crucial. This review aims to summarize infertility risk related to currently available breast cancer treatment, options for fertility preservation and its details, barriers to oncofertility counseling, and psychosocial issues.

Impact of Breast Cancer and Germline BRCA Pathogenic Variants on Fertility Preservation in Young Women

BACKGROUND

Several studies have suggested that breast cancer (BC) and germline BRCA pathogenic variants (gBRCA PVs) could have a deleterious impact on ovarian reserve. Nevertheless, data are limited and mixed. Our objective was to evaluate the performance of fertility preservation (FP) in terms of the number of collected mature oocytes after ovarian stimulation (OS) in young women carrying a gBRCA PV, associated or not with BC.

METHODS

We conducted a retrospective monocentric study at HUB-Hôpital Erasme in Brussels. All women aged between 18 and 41 years diagnosed with invasive non-metastatic BC and/or gBRCA PV carriers who underwent OS for FP or preimplantation genetic testing for monogenic disorder (PGT-M) between November 2012 and October 2021 were included. Three groups were compared: BC patients without a gBRCA PV, BC patients with a gBRCA PV, and healthy gBRCA PV carriers. Ovarian reserve was evaluated based on the efficacy of OS and AMH levels.

RESULTS

A total of 85 patients underwent 100 cycles. The mean age (32.2 ± 3.9 years; p = 0.61) and median AMH level (1.9 [0.2-13] μg/L; p = 0.22) were similar between groups. Correlations between the number of mature oocytes and AMH level (p < 0.001) and between AMH and age (p < 0.001) were observed. No differences in the number of retrieved mature oocytes were observed between groups (p = 0.41), or for other OS parameters.

CONCLUSION

Neither BC nor a gBRCA PV significantly affects ovarian reserve and FP efficacy in terms of the number of mature oocytes retrieved.

Response to Ovarian Stimulation for Urgent Fertility Preservation before Gonadotoxic Treatment in BRCA-Pathogenic-Variant-Positive Breast Cancer Patients

BRCA 1/2 pathogenic variants increase the risk of developing early and aggressive breast cancers (BC). For these patients, fertility potential can be directly affected by oncologic treatments. In addition, evidence indicates that BRCA-mutated women had a significant reduction in their ovarian reserve. In order to improve their chances of conception after the completion of cancer treatments, fertility preservation should be proposed before the administration of gonadotoxic drugs, ideally by oocyte vitrification after controlled ovarian hyperstimulation (COH). The present investigation aims to assess the ovarian response to COH in BRCA 1/2-pathogenic-variant carriers diagnosed with BC. Patient characteristics and COH outcomes were compared between BRCA-positive (n = 54) and BRCA-negative (n = 254) patients. The number of oocytes recovered did not differ between the two groups. However, the oocyte maturation rate and the number of mature oocytes obtained (7 (4.5-11.5) vs. 9 (5-14) oocytes, p = 0.05) were significantly lower in the BRCA-mutated patients. Although individualized COH protocols should be discussed, BRCA-mutated patients would benefit from FP before BC occurs, in order to cope with the potential accelerated decline of their ovarian reserve, optimize the success rate of FP by repeating COH cycles, and to preserve the feasibility of PGT-M by collecting a large amount of eggs.

Should Preimplantation Genetic Testing (PGT) Systematically Be Proposed to BRCA Pathogenic Variant Carriers?

Over the past years, BRCA genes pathogenic variants have been associated to reproductive issues. Indeed, evidence indicate that BRCA-mutated patients are not only at higher risk of developing malignancies, but may also present a reduction of the follicular stockpile. Given these characteristics, BRCA patients may be candidates to fertility preservation (FP) techniques or preimplantation genetic testing (PGT) to avoid the transmission of this inherited situation. Since the success rates of both procedures are highly related to the number of oocytes that could be recovered after ovarian stimulation, predicted by ovarian reserve tests, they are ideally performed before the diagnosis of cancer and its treatment. Despite the specific reproductive challenges related to BRCA status, no international guidelines for the application of PGT and FP in this subgroup of patients is currently available. The present article aims to review the available data regarding BRCA carriers' ovarian reserve and PGT success rates in oncologic and non-oncologic contexts, to determine the actual indication of PGT and further to improve patients' care pathway.

Ovarian reserve in premenopausal women with breast cancer

Background

As a special reproductive hormone and ovarian reserve indicator, the role of anti-Müllerian hormone (AMH) in premenopausal women with breast cancer deserves further study.

Methods

We conducted an in-depth analysis of the data from the EGOFACT study (NCT02518191), a phase Ⅲ, randomized, controlled trial involving premenopausal female breast cancer patients in two parallel groups: chemotherapy with or without gonadotropin-releasing hormone analogs (GnRHa). Three hundred thirty premenopausal women aged 25–49 years with operable stage I to III breast cancer were included in this study. The characteristics of ovarian reserve changes marked by AMH in the EGOFACT study and the factors affecting ovarian function in premenopausal women with breast cancer were analyzed.

Results

The AMH level of the chemotherapy alone group decreased gradually within one year, while the AMH level of the GnRHa group was significantly higher as early as 6 months after chemotherapy and recovered to close to the baseline level 12 months after chemotherapy (F = 34.991, P < 0.001). Correlation analysis showed that the factors affecting AMH levels mainly included age, menarche age, body mass index (BMI), reproductive history, baseline follicle stimulating hormone (FSH) level, pathological stage and GnRHa application, but they had different effects on the incidence of premature ovarian insufficiency (POI) at different periods. Multivariate logistic regression analysis showed that menarche age younger than 14 years (OR 0.470 [0.259, 0.852], P = 0.013), baseline AMH level higher than 0.5 ng/mL (OR 9.590 [3.366, 27.320], P < 0.001), pathological stage Ⅰ(OR 0.315 [0.124, 0.798], P = 0.015) and GnRHa application (OR 0.090 [0.045, 0.183], P < 0.001) were independent factors conducive to protection of ovarian reserve, as well as to recovery of ovarian reserve.

Conclusions

Age, menarche age, baseline AMH level, and GnRHa application are the most important influencing factors for ovarian reserve in premenopausal women with breast cancer.

Trial registration

ClinicalTrials.gov, NCT02518191, registered on Aug 5, 2015.

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GnRHa can reverse the trend of ovarian reserve changes and reduce the risk of POI after chemotherapy.

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Premenopausal patients younger than 35 years old had higher AMH levels and were less likely to develop primary or secondary POI.

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Premenopausal patients with menarche earlier than 14 years old had higher AMH levels and were less likely to develop POI after chemotherapy.

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Premenopausal patients with BMI<25 received chemotherapy alone or those with BMI≥25 received chemotherapy+GnRHa were more likely to develop POI.