Infertility, treatment of infertility, and the risk of breast cancer among women with BRCA1 and BRCA2 mutations: a case-control study

IVF and breast cancer: a systematic review and meta-analysis

BACKGROUND

The effects of controlled ovarian hyperstimulation (COH) for IVF in terms of breast cancer risk remain controversial, despite the hormone-dependent nature of the latter.

METHODS

Eligible studies up to 15 February 2013 were identified and pooled effect estimates for relative risk (RR) were calculated separately for the investigations using the general population and those using infertile women, as a reference group. Fixed- or random-effects models were implemented and subgroup analyses were performed, as appropriate.

RESULTS

Eight cohort studies were synthesized, yielding a total cohort size of 1,554,332 women among whom 14,961 incident breast cancer cases occurred, encompassing 576 incident breast cancer cases among women exposed to IVF. No significant association between IVF and breast cancer was observed either in the group of studies treating the general population (RR = 0.91, 95% confidence interval (CI): 0.74-1.11) or infertile women (RR = 1.02, 95% CI: 0.88-1.18), as a reference group. Of note were the marginal associations, protective for pregnant and/or parous women after IVF (pooled effect estimate = 0.86, 95% CI: 0.73-1.01) and adverse for women <30 years at first IVF treatment (pooled effect estimate = 1.64, 95% CI: 0.96-2.80).

CONCLUSIONS

At present, COH for IVF does not seem to impart increased breast cancer risk. Longer follow-up periods, comparisons versus infertile women, subgroup analyses aiming to trace vulnerable subgroups, adjustment for various confounders and larger informative data sets are needed before conclusive statements for the safety of the procedure are reached.

PGD for hereditary breast and ovarian cancer: the route to universal tests for BRCA1 and BRCA2 mutation carriers

Preimplantation Genetic Diagnosis (PGD) is a method of testing in vitro embryos as an alternative to prenatal diagnosis with possible termination of pregnancy in case of an affected child. Recently, PGD for hereditary breast and ovarian cancer caused by BRCA1 and BRCA2 mutations has found its way in specialized labs. We describe the route to universal single-cell PGD tests for carriers of BRCA1/2 mutations. Originally, mutation-specific protocols with one or two markers were set up and changed when new couples were not informative. This route of changing protocols was finalized after 2 years with universal tests for both BRCA1 and BRCA2 mutation carriers based on haplotyping of, respectively, 6 (BRCA1) and 8 (BRCA2) microsatellite markers in a multiplex PCR. Using all protocols, 30 couples had a total of 47 PGD cycles performed. Eight cycles were cancelled upon IVF treatment due to hypostimulation. Of the remaining 39 cycles, a total of 261 embryos were biopsied and a genetic diagnosis was obtained in 244 (93%). In 34 of the 39 cycles (84.6%), an embryo transfer was possible and resulted in 8 pregnancies leading to a fetal heart beat per oocyte retrieval of 20.5% and a fetal heart beat per embryonic transfer of 23.5%. The preparation time and costs for set-up and validation of tests are minimized. The informativity of microsatellite markers used in the universal PGD-PCR tests is based on CEPH and deCODE pedigrees, making the tests applicable in 90% of couples coming from these populations.

Fertility medications and the risk of cancer

Cancer is among the leading causes of death, and malignant diseases of the female genital tract are among the most common sites. Reproductive factors that are also associated with infertility have been identified as risk factors. Hormones are thought to play a role in the induction and promotion of some type of cancers. Hormonal preparations affect the endocrine milieu and, by acting on the reproductive organs themselves, could even have a direct effect on carcinogenesis. Numerous case-control and cohort studies have tried to determine whether fertility medication use increases cancer risk. Overall, the current data is reassuring but most research groups drew conclusions based on a small number of cases and after a relatively short follow-up. Proper counseling prior to fertility medication use is important and further studies on even larger patient groups with more cancer cases are needed to support widespread use of fertility medications.

Fertility preservation in young breast cancer patients: addressing individual patient needs

SUMMARY In female patients, infertility may be regarded as an essential loss of femininity and infertility after cancer, and is known to be associated with psychosocial distress. Fertility preservation is thus an important issue for young women diagnosed with breast cancer. Nevertheless, breast cancer patients have traditionally not been offered the most well-established methods for fertility preservation, such as embryo and oocyte freezing, as a rise in estradiol during standard stimulation protocols has been regarded as potentially deleterious in these patients. Alternative protocols for stimulation, such as those using tamoxifen and aromatase inhibitors, have therefore been developed. Protocols including aromatase inhibitors have been demonstrated to be more effective than those using tamoxifen in terms of the number of oocytes and embryos obtained, while maintaining estradiol levels within the normal range of a menstrual cycle. Cryopreservation of immature oocytes and ovarian cortical tissue are methods that are still under development. Reports of children born after application of these experimental methods are currently increasing and these methods are thus gaining a place within the options for fertility preservation in breast cancer patients.

Meta-Analysis on the Possible Association Between In Vitro Fertilization and Cancer Risk

Objective

We aimed to examine the association between in vitro fertilization (IVF) and risk of cancers through conducting a meta-analysis of cohort studies.

Methods

Relevant studies were identified by using PubMed, ISI Web of knowledge, and Scopus through March 2012. Reference lists from retrieved articles were also reviewed. We included historical cohort studies that reported relative risks (RRs) with 95% confidence intervals (CIs) for the association between IVF and cancer risk. Both fixed- and random-effects models were used to calculate the summary risk estimates.

Results

Eight cohort studies involving 746,455 participants were included in this meta-analysis. The overall combined RRs for women with IVF treatment were 0.99 (95% CI, 0.74–1.32) for all-site cancer, 1.59 (95% CI, 1.24–2.03) for ovarian cancer, 0.89 (95% CI, 0.79–1.01) for breast cancer, and 1.07 (95% CI, 0.45–2.55) for cervical cancer. A beneficial effect was shown in the subgroup of breast cancer meta-analysis compared with women who gave birth (RR, 0.79; 95% CI, 0.65–0.95). Excess risk of ovarian cancer was still observed when analyses were restricted to studies with less than 8 years of follow-up (RR, 2.35; 95% CI, 1.03–5.37) and studies including cancer cases diagnosed within 1 year of the IVF treatment (RR, 1.71; 95% CI, 1.22–2.40). No evidence of substantial publication bias was observed.

Conclusions

This meta-analysis suggests that there is no significant association between IVF and cancer risk. A possible beneficial effect was shown in the subgroup of breast cancer meta-analysis. Excess risk of ovarian cancer was observed in the analysis of all the studies and subgroups. Special attention should be made to women who may be diagnosed with cancer during or shortly after IVF treatment. Studies of high methodological quality with larger population and longer follow-up are required to provide more evidences for a better understanding of the association.

Breast cancer and fertility

OPINION STATEMENT

The increased availability of assisted reproductive technologies (ART) allows women with fertility issues to increase their chances of a successful pregnancy with the use of medications that, in some cases, increase circulating estrogens. There has been significant concern that the use of these medications will increase the risk of hormone-sensitive cancers such as breast, ovarian and uterine malignancies. Additionally, for those women who are diagnosed with a breast cancer during their reproductive years, this diagnosis can be particularly difficult as future fertility is a major concern for many young breast cancer survivors. With the current available data, there does not appear to be a statistically significant increase in the risk of developing breast cancer with ART, although several series suggest a potential possible related increase in borderline ovarian and uterine cancers. For breast cancer survivors, there does not appear to be an increased risk of death associated with subsequent pregnancies when compared with breast cancer patients who did not have subsequent pregnancies, although waiting at least 2 years after the diagnosis of breast cancer potentially may convey a protective effect. Therefore, when systemic therapy for breast cancer is recommended, early counseling and referral to a reproductive endocrinologist is warranted to provide optimal fertility preservation options. Further safety and outcomes studies are warranted for children.

Fertility preservation and pregnancy in women with and without BRCA mutation-positive breast cancer

Women with breast cancer face many challenges when considering fertility preservation. Delayed referral results in the limitation of fertility preservation options because most established methods, such as embryo and oocyte cryopreservation, require several weeks to complete. Women with BRCA mutations, on the other hand, may be more aware of fertility issues and motivated to see fertility preservation specialists earlier. Fear of exposure to estrogen limits access to fertility preservation via embryo or oocyte cryopreservation; however, the use of aromatase inhibitors as ovarian stimulants reduces such concern. Ovarian cryopreservation can be used when there is insufficient time to perform ovarian stimulation because this technique does not require hormonal stimulation, but there are safety concerns both in women with BRCA mutations and in patients with hormone receptor-positive disease as well. There does not seem to be a proven ovarian suppression strategy to preserve fertility in women with breast cancer. Pregnancy appears to be safe for breast cancer survivors but studies specific for women with BRCA mutations are lacking. Women with BRCA mutations may elect to use preimplantation genetic diagnosis during in vitro fertilization to avoid transmitting the mutation, but there may be psychosocial difficulties in entertaining this option. Overall, the last decade has brought many options for women with breast cancer considering fertility preservation, but numerous challenges remain. The presence of BRCA mutations further contributes to these challenges.

Fertility drugs and young-onset breast cancer: results from the Two Sister Study

BACKGROUND

Fertility drugs stimulate hyperovulation, which may have implications for breast cancer. We examined the association between use of fertility drugs (clomiphene citrate [CC] and follicle-stimulating hormone [FSH]) and subsequent risk of young-onset (<50 years at diagnosis) breast cancer.

METHODS

We conducted the Two Sister Study, a sister-matched case-control study, by enrolling 1422 women between September 2008 and December 2010, who were younger than age 50 years at diagnosis with breast cancer and were enrolled within 4 years of diagnosis, and 1669 breast cancer-free control sisters from the Sister Study. Participants reported their use of fertility drugs (CC and FSH) and ever-users reported whether a pregnancy had resulted that lasted 10 or more (10+) weeks. Conditional logistic regression was used to estimate confounder-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for fertility drug use with or without conception of a 10+ week pregnancy.

RESULTS

A total of 288 participants reported having used ovulation-stimulating drugs (193 CC only, 29 FSH only, and 66 both). Overall, women who had used fertility drugs showed a non-statistically significantly decreased risk of breast cancer, compared with nonusers (OR = 0.82, 95% CI = 0.63 to 1.08). Women who had used fertility drugs but had not conceived a 10+ week pregnancy under treatment showed a statistically significantly decreased risk of breast cancer compared with nonusers (OR = 0.62, 95% CI = 0.43 to 0.89). Women who had used fertility drugs and conceived a 10+ week pregnancy under treatment showed a statistically significantly increased risk of breast cancer compared with unsuccessfully treated women (OR = 1.82, 95% CI = 1.10 to 3.00), although their risk was not increased compared with women who had not used fertility drugs (OR = 1.13, 95% CI = 0.78 to 1.64).

CONCLUSIONS

In the absence of a 10+ week pregnancy under treatment, exposure to ovulation-stimulating fertility drugs was associated with reduced risk of young-onset breast cancer. This apparent association was absent in women who conceived a 10+ week pregnancy under treatment, for whom risk was higher than that of unsuccessfully treated women, but similar to that of untreated women.

Fertility drugs and the risk of breast and gynecologic cancers

The evaluation of cancer risk among patients treated for infertility is complex, given the need to consider indications for use, treatment details, and the effects of other factors (including parity status) that independently affect cancer risk. Many studies have had methodologic limitations. Recent studies that have overcome some of these limitations have not confirmed a link between drug use and invasive ovarian cancers, although there is still a lingering question as to whether borderline tumors might be increased. It is unclear whether this merely reflects increased surveillance. Investigations regarding breast cancer risk have produced inconsistent results. In contrast, an increasing number of studies suggest that fertility drugs may have a special predisposition for the development of uterine cancers, of interest given that these tumors are recognized as particularly hormonally responsive. Additional studies are needed to clarify the effects on cancer risk of fertility drugs, especially those used in conjunction with in vitro fertilization. Because many women who have received such treatments are still relatively young, further monitoring should be pursued in large well-designed studies that enable assessment of effects within a variety of subgroups defined by both patient and disease characteristics.

Long-term complications of assisted reproductive technologies

Since the birth of the first baby through in vitro fertilisation over 30 years ago, there has been a rapid increase in the number of women using assisted reproductive technologies. New techniques are constantly being introduced and are evolving rapidly. Understanding the long-term impact of these treatments, which have been linked with several potential complications affecting the mother and the child, poses a constant challenge for the scientific community. The main complications discussed in this review include the rare but serious risk of thromboembolic disease particularly in the upper half of the body and a higher risk of pregnancy complications including abnormal placentation, miscarriage, gestational diabetes and hypertensive disorders. A link between assisted conception and a number of genital cancers particularly of the breast, ovary and endometrium has also been suggested, but the evidence is currently inconclusive. A number of foetal and neonatal complications including imprinting disorders, low birth weight, congenital malformations and growth disorders are also discussed.

Fertility preservation in women with breast cancer

Fertility preservation is an important issue for young women diagnosed with breast cancer. The most well-established options for fertility preservation in cancer patients, embryo and oocyte cryopreservation, have not been traditionally offered to breast cancer patients as estradiol rise during standard stimulation protocols may not be safe for those patients. Potentially safer stimulation protocols using tamoxifen and aromatase inhibitors induce lower levels of estradiol whereas similar results in terms of number of oocyte and embryo obtained to standard protocols. Cryopreservation of immature oocytes and ovarian cortical tissue, both still experimental methods, are also fertility preservation options for breast cancer patients.

The effects of parity, breastfeeding, and infertility treatment on the risk of hereditary breast and ovarian cancer: a review

Knowledge of the potential association of parity, breastfeeding, and infertility treatment on breast and ovarian cancer risk for BRCA1 and BRCA2 mutation carriers is important and should be a crucial part of genetic counseling. The discussion of parity and clinical management of infertility in these women is complex, and patient preferences should be considered. Ideally, these preferences should be informed by accurate information on the risks and benefits of the interventions considered. However, this important subject has been investigated in a relatively small number of studies, thus, the existing data remain somewhat limited, and the estimated risk of cancer in BRCA mutation carriers is imprecise.

Surviving childhood and reproductive-age malignancy: effects on fertility and future parenthood

Annually, more than 50,000 cancer diagnoses are made in the USA in patients under the age of 35 years. Despite this staggering statistic, medical advancements have substantially improved survival rates. Thus, for both male and female patients with cancer, quality-of-life issues, such as fertility preservation and parenthood, have become an essential component of treatment. Unfortunately, many of the treatments to eradicate malignant processes can also compromise reproductive function. In these cases, fertility preservation should be discussed and initiated with early treatment planning, to allow the best chance for future parenthood, when appropriate. The effects of cancer and cancer treatments on fertility and future parenthood, including health risks for patients, their gametes, and offspring are discussed.

Preimplantation genetic diagnosis for BRCA1/2--a novel clinical experience

OBJECTIVE

To describe our 2-year experience with preimplantation genetic diagnosis (PGD) for carriers of mutations in the genes BRCA1 and BRCA2, the dilemmas incurred and the lessons learned.

METHODS

We collected data on those carriers of BRCA1/2 mutations who applied for PGD counseling and who decided to proceed. We describe the PGD procedures that were conducted and their outcome.

RESULTS

Ten carriers of BRCA1/2 mutations applied for PGD counseling, seven were healthy, and three were BC survivors. Eight women needed in vitro fertilization (IVF) because of coexisting infertility. After counseling, six opted for the procedure and five of them underwent PGD for the BRCA mutation. In one of these PGD, fluorescence in situ hybridization (FISH) analysis for chromosomes 21, X and Y was also performed. Three women conceived, each in the first treatment attempt. One of them gave birth to twins, the second to a singleton and the third is currently pregnant. During the pregnancies, dilemmas concerning PGD confirmation were discussed.

CONCLUSIONS

PGD is an acceptable reproductive option for BRCA mutation carriers, especially for those who require IVF due to fertility problems. Discussion of this option should be carried out with sensitivity, taking into account the age of the woman, her health, fertility status and emotional state. Confirmatory prenatal diagnosis may not always be encouraged.