Prognostic role of pregnancy occurring before or after treatment of early breast cancer patients aged <35 years: a GET(N)A Working Group analysis

Prognostic effect of subsequent childbirth after the diagnosis of breast cancer using propensity score matching analysis

BACKGROUND

Among younger patients, one of the important concerns is whether they can give birth safely. Although previous studies have investigated this topic, many aspects remain unclear owing to potential biases. We aimed to evaluate the prognostic effect of subsequent childbirth after the diagnosis using propensity score matching.

METHODS

A single-center retrospective cohort study was conducted. This study included patients aged ≤ 45 years, diagnosed with breast cancer between 2005 and 2014. Patients with and without subsequent childbirth were assigned to the childbirth and non-childbirth cohorts, respectively. Relapse-free survival (RFS) and overall survival (OS) of the childbirth cohort were compared with those of the non-childbirth cohort. The covariates in the propensity score model included age, tumor size, node status, number of preceding childbirths before the diagnosis, estrogen receptor, and human epidermal growth factor receptor 2 status.

RESULTS

104 patients with childbirth and 2250 without childbirth were assigned to the respective cohorts. At a median follow-up of 82 months, the childbirth cohort showed a significantly longer RFS than the non-childbirth cohort (HR = 0.469 [0.221-0.992]; p = 0.047). There was no significant difference in the OS (HR = 0.208 [0.029-1.494]; p = 0.119). After matching, subsequent childbirth was not significantly associated with RFS (HR = 0.436 [0.163-1.164], p = 0.098) and OS (HR = 0.372 [0.033-4.134], p = 0.402).

CONCLUSIONS

Subsequent childbirth was not associated with an increased risk of relapse and mortality. It is important to make younger patients aware of these novel findings and aid them in their decision-making.

Update on Pregnancy Following Breast Cancer Diagnosis and Treatment

ABSTRACT

Survivorship has become a crucial component in breast cancer care. For women who have not completed their family planning, conceiving at the end of anticancer treatments should not be discouraged but might be challenging. Oncofertility counseling should be offered at the time of diagnosis to all patients, in order to inform them about the potential treatment-induced gonadotoxicity as well as the available strategies for fertility preservation, thus allowing to increase the chances of a future pregnancy. This article reports an updated overview on the current state of the art on pregnancy in women with prior breast cancer diagnosis and treatment, with a main focus on the issues faced by patients with history of hormone receptor-positive disease and BRCA carriers.

Pregnancy After Breast Cancer: A Systematic Review and Meta-Analysis

PURPOSE

Many patients and physicians remain concerned about the potential detrimental effects of pregnancy after breast cancer (BC) in terms of reproductive outcomes and maternal safety. This systematic review and meta-analysis aimed at providing updated evidence on these topics.

METHODS

A systematic literature review was conducted to identify studies including patients with a pregnancy after BC (PROSPERO number CRD42020158324). Likelihood of pregnancy after BC, their reproductive outcomes, and maternal safety were assessed. Pooled relative risks, odds ratios (ORs), and hazard ratios (HRs) with 95% CIs were calculated using random effects models.

RESULTS

Of 6,462 identified records, 39 were included involving 8,093,401 women from the general population and 112,840 patients with BC of whom 7,505 had a pregnancy after diagnosis. BC survivors were significantly less likely to have a subsequent pregnancy compared with the general population (relative risk, 0.40; 95% CI, 0.32 to 0.49). Risks of caesarean section (OR, 1.14; 95% CI, 1.04 to 1.25), low birth weight (OR, 1.50; 95% CI, 1.31 to 1.73), preterm birth (OR, 1.45; 95% CI, 1.11 to 1.88), and small for gestational age (OR, 1.16; 95% CI, 1.01 to 1.33) were significantly higher in BC survivors, particularly in those with previous chemotherapy exposure, compared with the general population. No significantly increased risk of congenital abnormalities or other reproductive complications were observed. Compared to patients with BC without subsequent pregnancy, those with a pregnancy had better disease-free survival (HR, 0.66; 95% CI, 0.49 to 0.89) and overall survival (HR, 0.56; 95% CI, 0.45 to 0.68). Similar results were observed after correcting for potential confounders and irrespective of patient, tumor, and treatment characteristics, pregnancy outcome, and timing of pregnancy.

CONCLUSION

These results provide reassuring evidence on the safety of conceiving in BC survivors. Patients' pregnancy desire should be considered a crucial component of their survivorship care plan.

Success and risks of pregnancy after breast cancer

INTRODUCTION

Breast cancer is the most common cancer in women worldwide. The number of childbearing-age women diagnosed with early breast cancer (eBC) is increasing, raising questions over their subsequent fertility.

PURPOSE

The main objective of this study was therefore to assess, in a cohort of eBC patients with pregnancy desire, the rate of live births achieved spontaneously or by assisted reproductive technology.

METHODS

We conducted an observational, descriptive, retrospective study including patients aged 18-40, treated for eBC at the Institut de Cancérologie de l'Ouest (ICO) Pays de Loire between July 2010 and July 2016, with pregnancy desire. The primary outcome was the rate of live births. Secondary outcomes were overall survival, disease-free survival, time to conception, and spontaneous or assisted pregnancy rate.

RESULTS

61 patients were included, with a live birth rate of 19.7% (12/61). We observed no recurrence or death in women with a pregnancy. Pregnancy started with a median time of 36.4 months after the end of treatment (4.1-51.3 months). All pregnancies in this cohort were achieved spontaneously.

CONCLUSION

The results of our cohort are consistent with previous results showing that spontaneous pregnancy remains possible after treatment for eBC without increasing the risk of recurrence or death.

Pregnancy in Breast Cancer Survivors

Safety of pregnancy occurring after breast cancer treatment has been studied largely, but it is still debatable. These studies have generally showed that overall and disease-free survival in breast cancer survivors with subsequent pregnancy is not less than those without future pregnancy . Also, breast cancer survivors treated with chemotherapy , radiation therapy, or both had no increased risk of congenital anomalies, single gene disorders, or chromosomal syndromes in their offspring. However, it appears that the incidence of preterm labor, low birth weight, and fetal anomalies is higher in these cases.These issues as well as safe time interval from breast cancer treatment to pregnancy , safe contraceptive method after breast cancer, counseling about pregnancy in survivors, and how to follow up the patient for breast cancer recurrence during pregnancy are discussed in this chapter.

Prognosis of pregnancy-associated breast cancer: a meta-analysis

BACKGROUND

Pregnancy-associated breast cancer (PABC) is defined as breast cancer that is diagnosed during pregnancy and/or the postpartum period. Definitions of the duration of the postpartum period have been controversial, and this variability may lead to diverse results regarding prognosis. Moreover, evidence on the dose-response association between the time from the last pregnancy to breast cancer diagnosis and overall mortality has not been synthesized.

METHODS

We systematically searched PubMed, Embase, and the Cochrane Library for observational studies on the prognosis of PABC published up to June 1, 2019. We estimated summary-adjusted hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs). Subgroup analyses based on diagnosis time, PABC definition, geographic region, year of publication and estimation procedure for HR were performed. Additionally, dose-response analysis was conducted by using the variance weighted least-squares regression (VWLS) trend estimation.

RESULTS

A total of 54 articles (76 studies) were included in our study. PABC was associated with poor prognosis for overall survival (OS), disease-free survival (DFS) and cause-specific survival (CSS), and the pooled HRs with 95% CIs were 1.45 (1.30-1.63), 1.39 (1.25-1.54) and 1.40 (1.17-1.68), respectively. The corresponding reference category was non-PABC patients. According to subgroup analyses, the varied definition of PABC led to diverse results. The dose-response analysis indicated a nonlinear association between the time from the last delivery to breast cancer diagnosis and the HR of overall mortality (P < 0.001). Compared to nulliparous women, the mortality was almost 60% higher in women with PABC diagnosed at 12 months after the last delivery (HR = 1.59, 95% CI 1.30-1.82), and the mortality was not significantly different at 70 months after the last delivery (HR = 1.14, 95% CI 0.99-1.25). This finding suggests that the definition of PABC should be extended to include patients diagnosed up to approximately 6 years postpartum (70 months after the last delivery) to capture the increased risk.

CONCLUSION

This meta-analysis suggests that PABC is associated with poor prognosis, and the definition of PABC should be extended to include patients diagnosed up to approximately 6 years postpartum.

Sexuality, fertility and pregnancy following breast cancer treatment

For women facing a new diagnosis of breast cancer, treatments can result in changes to intimate issues, including sexual health. For women of reproductive age, other significant concerns include the potential impact on fertility and the safety of pregnancy after treatment. These issues are important to acknowledge and to address, as they can impact on quality of life, not only for the patient, but may impact relationships, both present and future. In this paper we review sexual health after cancer, the importance of proactively addressing fertility, and important issues related to pregnancy following breast cancer.

[Do controlled ovarian hyperstimulations and cryopreservations promote recurrences after breast cancer?]

The objective of this review was to identify recurrences (ipsilateral, contralateral, metastases and deaths) occurring after controlled ovarian hyperstimulation (COH) or cryopreservation of ovarian tissue (CPTO) for patients treated for a breast cancer.

METHODS

We performed a bibliographical research through the Pubmed/Medline database, including all the references from January 2006 until September 2016, in French or in English, after exclusion of animal studies. The keywords association "breast neoplasms", "fertility preservation", "reproductive techniques", "ovarian cryopreservation" and "in vitro fertilization" allowed the selection of 852 publications among which only 6 were selected because they included data on recurrence and long term follow up. Four publications involved HSC (3 before breast cancer treatment and 1 after) and 2 concerned CPTO with re-implantation.

RESULTS

This analysis has not shown increasing of breast recurrences after HSC and CPTO. However, results were not statistically significant, due to several biases in particular heterogeneousness of the groups of patients.

CONCLUSION

A survey of patients who used fertility preservation or assisted reproductive technologies after breast cancer would be helpful to better estimate their oncological risk.

Safety of pregnancy after surgical treatment for breast cancer: a meta-analysis

PURPOSE

Because of the rising trend of delayed pregnancies, more and more women remain nulliparous at the diagnosis of breast cancer, and approximately 71% of them desire to conceive after breast cancer treatment. Advances in breast cancer screening have made early diagnosis of breast cancer possible, and many patients have the opportunity to be treated by surgery. In this study, we conducted a meta-analysis to evaluate the effect of pregnancy on patient survival and prognosis after surgical treatment for breast cancer.

METHODS

An electronic search was performed in MEDLINE (PubMed), EMBASE, and Web of Science to identify potentially eligible studies published before August 2013. Both fixed-effect and random-effect models were used to calculate the pooled relative risk (PRR). The Q test and I(2) statistics were used to assess the heterogeneity among the studies.

RESULTS

A total of 5 studies were included in our meta-analysis. Five hundred fifty-four patients who become pregnant after surgical treatment for breast cancer were compared with a control group of 2354 patients for overall survival (OS). Our analysis demonstrated that pregnancy after surgical treatment for breast cancer had a significant beneficial effect on OS (PRR, 0.78; 95% confidence interval, 0.64-0.95). The disease-free survival outcome also favored patients in the pregnancy group (PRR, 0.87; 95% confidence interval, 0.71-1.08).

CONCLUSIONS

This meta-analysis indicates that pregnancy after surgical treatment does not increase the risk of breast cancer recurrence and may actually improve OS.

Outcome of patients with pregnancy during or after breast cancer: a review of the recent literature

BACKGROUND

An increasing number of young women are delaying childbearing; hence, more are diagnosed with breast cancer (bca) before having a family. No clear recommendations are currently available for counselling such a population on the safety of carrying a pregnancy during bca or becoming pregnant after treatment for bca.

METHODS

Using a Web-based search of PubMed we reviewed the recent literature about bca and pregnancy. Our objective was to report outcomes for patients diagnosed with bca during pregnancy, comparing them with outcomes for non-pregnant women, and to evaluate prognosis in women diagnosed with and treated for bca who subsequently became pregnant.

RESULTS

"Pregnancy and bca" should be divided into two entities. Pregnancy-associated bca tends to be more aggressive and advanced in stage at diagnosis than bca in control groups; hence, it has a poorer prognosis. With respect to pregnancy after bca, there is, despite the bias in reported studies and meta-analyses, no clear evidence for a different or worse disease outcome in bca patients who become pregnant after treatment compared with those who do not.

CONCLUSIONS

Pregnancy-associated bca should be treated as aggressively as and according to the standards applicable in nonpregnant women; pregnancy after bca does not jeopardize outcome. The guidelines addressing risks connected to pregnancy and bca lack a high level of evidence for better counselling young women about pregnancy considerations and preventing unnecessary abortions. Ideally, evidence from large prospective randomized trials would set better guidelines, and yet the complexity of such studies limits their feasibility.

Fertility preservation and breast cancer: a review

Breast cancer is the most common malignancy in women, and its incidence increases with age, with the majority of patients diagnosed after menopause. However, in 15–25% of cases, patients are premenopausal at the time of diagnosis, and about 7% of them are below the age of 40. Therefore, a considerable amount of young women are diagnosed with breast cancer during their reproductive life. Within this group, most cancer cases require cytotoxic chemotherapy and/or hormone therapy, which are responsible for a decrease in the patients’ reproductive function, along with their age. The efficacy of such treatments, among other factors, has led to a high five-year-survival rate, which results in an increasing number of young women who survive breast cancer before having fulfilled their reproductive wishes, especially considering the current trend to delay pregnancy until the late 30s or early 40s in developed countries. The combination of these factors justifies the importance of fertility preservation and reproductive counselling at the time of breast cancer diagnosis in young women.

A wide range of fertility preservation techniques has been developed, such as ovarian suppression, oocyte and embryo cryopreservation, immature oocyte retrieval and in vitro maturation, and ovarian tissue cryopreservation.

Early counselling and referral of these patients to fertility specialists are fundamental factors in order to maximise their chances of pregnancy. This review aims to update the knowledge about the influence of breast cancer in fertility, the influence of pregnancy and fertility preservation techniques in breast cancer patients and assessment of ovarian reserve for a better treatment choice. A special section dedicated to BRCA-mutation carriers has been included because of their specific features.

A comprehensive literature search has been conducted, including publications from the last five years.

Preserving fertility in patients undergoing treatment for breast cancer: current perspectives

Invasive breast cancer (BC) is the most frequent cancer of young women. Considering the trend toward postponing childbearing until the later reproductive years, the number of childless women at diagnosis of BC will continue to increase. The American Society of Clinical Oncology and the American Society for Reproductive Medicine have recommended that the impact of cancer treatments on fertility should be addressed with all cancer patients of reproductive age and that options for fertility preservation, such as cryopreservation of embryos and oocytes, ovarian tissue, in vitro maturation of immature oocytes, and ovarian suppression with gonadotropin-releasing hormone analogs, should be discussed routinely. To optimally counsel patients on how to best weigh the risks and benefits of fertility preservation, both the health care provider and the patient must know about the options, their risks, and their likelihood of success. The aim of this review is to summarize current knowledge on fertility preservation options for young BC patients, surrogates of ovarian function, psychosocial aspects of infertility after cancer treatment, women’s attitudes towards childbearing after cancer treatment, and health care providers’ attitudes towards fertility preservation.

Matching methods to create paired survival data based on an exposure occurring over time: a simulation study with application to breast cancer

Background

Paired survival data are often used in clinical research to assess the prognostic effect of an exposure. Matching generates correlated censored data expecting that the paired subjects just differ from the exposure. Creating pairs when the exposure is an event occurring over time could be tricky. We applied a commonly used method, Method 1, which creates pairs a posteriori and propose an alternative method, Method 2, which creates pairs in “real-time”. We used two semi-parametric models devoted to correlated censored data to estimate the average effect of the exposure HR¯(t): the Holt and Prentice (HP), and the Lee Wei and Amato (LWA) models. Contrary to the HP, the LWA allowed adjustment for the matching covariates (LWA_a) and for an interaction (LWA_i) between exposure and covariates (assimilated to prognostic profiles). The aim of our study was to compare the performances of each model according to the two matching methods.

Methods

Extensive simulations were conducted. We simulated cohort data sets on which we applied the two matching methods, the HP and the LWA. We used our conclusions to assess the prognostic effect of subsequent pregnancy after treatment for breast cancer in a female cohort treated and followed up in eight french hospitals.

Results

In terms of bias and RMSE, Method 2 performed better than Method 1 in designing the pairs, and LWA_a was the best model for all the situations except when there was an interaction between exposure and covariates, for which LWA_i was more appropriate. On our real data set, we found opposite effects of pregnancy according to the six prognostic profiles, but none were statistically significant. We probably lacked statistical power or reached the limits of our approach. The pairs’ censoring options chosen for combination Method 2 - LWA had to be compared with others.

Conclusions

Correlated censored data designing by Method 2 seemed to be the most pertinent method to create pairs, when the criterion, which characterized the pair, was an exposure occurring over time. In such a setting, the LWA was the most appropriate model.

The impact of pregnancy on breast cancer survival in women who carry a BRCA1 or BRCA2 mutation

Physicians are often approached by young women with a BRCA mutation and a recent history of breast cancer who wish to have a baby. They wish to know if pregnancy impacts upon their future risks of cancer recurrence and survival. To date, there is little information on the survival experience of women who carry a mutation in one of the BRCA genes and who become pregnant. From an international multi-center cohort study of 12,084 women with a BRCA1 or BRCA2 mutation, we identified 128 case subjects who were diagnosed with breast cancer while pregnant or who became pregnant after a diagnosis of breast cancer. These women were age-matched to 269 mutation carriers with breast cancer who did not become pregnant (controls). Subjects were followed from the date of breast cancer diagnosis until the date of last follow-up or death from breast cancer. The Kaplan-Meier method was used to estimate 15-year survival rates. The hazard ratio for survival associated with pregnancy was calculated using a left-truncated Cox proportional hazard model, adjusting for other prognostic factors. Among women who were diagnosed with breast cancer when pregnant or who became pregnant thereafter, the 15-year survival rate was 91.5 %, compared to a survival of 88.6 % for women who did not become pregnant (adjusted hazard ratio = 0.76; 95 % CI 0.31-1.91; p = 0.56). Pregnancy concurrent with or after a diagnosis of breast cancer does not appear to adversely affect survival among BRCA1/2 mutation carriers.

Effect of an event occurring over time and confounded by health status: estimation and interpretation. A study based on survival data simulations with application on breast cancer

Estimating the prognostic effect of a time-dependent covariate could be tricky using a classical Cox model, despite adjustment on other known prognostic factors. This study evaluated and compared the performance of a Cox model including the covariate occurring over time as a time-dependent covariate and the so-called 'illness-death' multistate model, which is usually used to describe event-history data. We assess breast cancer prognosis related to a subsequent pregnancy occurring over time after cancer treatment in young women. We generated simulations. We considered constant and time-varying prognostic hazard ratios ( HR(t)) between patients undergoing the intermediate event and those who did not. We used both the classical Cox model and the multistate model to estimate the prognostic effect of the intermediate event HR(t). We also used the latter to estimate the covariate effect on each transition (exp(β(ij) )), thus helping to interpret HR(t) by taking into account the disease history. We applied these approaches to a female cohort treated and followed up in eight French Hospitals since 1990.

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.

Pregnancy despite ovarian insufficiency in a patient with breast cancer

Future fertility is a concern for many young breast cancer survivors. Secondary amenorrhea occurs frequently during or soon after oncologic treatment. Return of menstruation and serum biomarkers are not absolute predictors of future fertility. We report a case of a 28 year old gravida 0 with recurrent Stage IIB invasive ductal breast carcinoma who managed to conceive twice despite showing clinical and biochemical signs of decreased ovarian reserve following treatment with chemotherapy and radiation. This case illustrates the potential for fertility in a patient with breast cancer despite chemotherapy-related amenorrhea and undetectable anti-Müllerian hormone levels. It exemplifies the imprecise nature of all clinical tests used to predict future fertility in breast cancer patients post-treatment. It should remind all providers to be careful in basing recommendations for childbearing on these surrogate endpoints.

Pregnancy after successful cancer treatment: what needs to be considered?

Over the last decade, advances in oncology led to improved treatment results and increasing numbers of long-term cancer survivors. Fulfilling the desire to have children is important for many patients after cancer treatment. Consequently, oncologists, gynecologists and obstetricians are seeing more patients who wish to conceive after treatment. The necessary prerequisites that should be considered when supporting a planned pregnancy after cancer treatment are discussed in this article. The possible consequences of chemotherapy and radiotherapy on the course of pregnancy and the health of the offspring, as well as the interactions between cancer and pregnancy, are reviewed with the focus on childhood cancer, malignant lymphomas, and breast cancer. Despite chemo- or radiotherapy, neither the teratogenic risk nor the risk of adventitious cancers appears to be increased for the offspring of cancer survivors. However, there is a slightly higher risk of miscarriage after chemotherapy. In case of radiation to the uterus, there is a higher risk of premature birth, intrauterine growth retardation, and increased perinatal mortality. The effect is more pronounced after prepubertal radiation than for postpubertal radiation. The former cancer patient's desire to conceive can nevertheless be supported, given that pregnancy and birth are closely monitored.

Motherhood after breast cancer: searching for la dolce vita

Advances in the field of adjuvant therapy in breast cancer have led to significant improvements in breast cancer survival. This has resulted in a progressive decline in breast cancer-related mortality, such that in 2010 there were estimated to be 400,000 breast cancer survivors under the age of 40 in the USA. Hence, enquiry into the feasibility of fertility preservation, subsequent pregnancy and breastfeeding is increasingly encountered. Fertility counseling remains suboptimal in breast cancer clinics, and there is a wide perception that pregnancy could worsen the prognosis of young breast cancer survivors, despite the lack of evidence supporting this notion. In addition, fertility preservation by means of embryo or oocyte cryopreservation requires ovarian stimulation, which is associated with a significant rise in estradiol levels and might delay initiation of therapy. All these factors, and others, have influenced the quality of fertility counseling offered to young breast cancer patients. In this article, we will critically analyze the available clinical and biological evidence on the safety and feasibility of pregnancy and breastfeeding following breast cancer. In addition, we will discuss the different fertility-preservation techniques available for these patients.

Safety of pregnancy after primary breast carcinoma in young women: a meta-analysis to overcome bias of healthy mother effect studies

BACKGROUND

An increased number of women are expected to conceive after the diagnosis of early breast cancer. Most physicians recommend that pregnancy be delayed by 2 to 3 years after diagnosis of early breast cancer, but this recommendation is based on data from trials with small patient cohorts. Furthermore, a healthy mother effect (HME) selection bias may be operative in most of these studies, because women undergoing childbearing after treatment were healthier when compared with the control group.

AIM

To perform a systematic review and meta-analysis of published trials corrected for HME bias so as to assess the effect of pregnancy (at least 10 months after diagnosis) versus no pregnancy on overall survival of primary breast cancer patients less than 45 years.

METHODS

We searched MEDLINE and Thomson Reuters (ISI) Web of Knowledge for eligible studies. From each study we extracted the relative hazard ratio or, if not provided, all the necessary data to impute it. In cases where the duration from diagnosis to pregnancy was not reported, we extracted relevant data to estimate it.

RESULTS

Our electronic search strategy yielded 1623 hits pertaining to 20 potentially eligible studies involving 49,370 premenopausal breast cancer patients. Ten studies were eligible after considering HME potential bias in matching controls. Among these, 9 studies (pregnant 1089, matched-controls 13051) contained data appropriate for analysis. Overall survival was statistically higher among patients who became pregnant compared to controls: fixed effect model estimated pooled hazard ratio for death 0.51 (95% confidence interval: 0.42-0.62). No study heterogeneity was observed: Q = 10.4, P = 0.17; I(2) = 48%.

CONCLUSION

The pooled available evidence indicates that in early breast cancer patients, pregnancy that occurs at least 10 months after diagnosis does not jeopardize prognosis and may actually confer significant survival benefit.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completing this CME activity, physicians should be better able to assess the effect pregnancy has on long-term survival in primary breast cancer patients under age 45; counsel patients on the safety of pregnancy after breast cancer diagnosis and treatment; and interpret how pregnancy may be associated with improved breast cancer survival.

Breast cancer and fertility preservation

OBJECTIVE

To review the benefits of adjuvant systemic therapy given to women with breast cancer of reproductive age, its effects on fertility, and options for fertility preservation.

DESIGN

Publications relevant to fertility preservation and breast cancer were identified through a PubMed database search.

CONCLUSION(S)

Most women who develop invasive breast cancer under age 40 will be advised to undergo adjuvant chemotherapy with or without extended antihormonal therapy to reduce the risk of recurrence and death from breast cancer. Adjuvant chemotherapy particularly with alkylating agents such as cyclophosphamide is gonadotoxic and markedly accelerates the rate of age-related ovarian follicle loss. Although loss of fertility is an important issue for young cancer survivors, there is often little discussion about fertility preservation before initiation of adjuvant therapy. Greater familiarity with prognosis and effects of different types of adjuvant therapy on the part of infertility specialists and fertility preservation options such cryopreservation of embryos, oocytes, and ovarian tissue on the part of oncologists would facilitate these discussions. Establishment of rapid fertility consultation links within cancer survivorship programs can help ensure that every young woman who is likely to undergo gonadotoxic cancer treatment is counseled about the effects of therapy and options available to her to increase the likelihood of childbearing after cancer treatment.

Pregnancy after breast cancer: case report and review of the literature

Despite breast cancer diagnosis and treatment, women of childbearing age often desire a pregnancy. Since the average age of women giving birth for the first time is increasing, many young patients diagnosed with breast cancer have not started or completed their family planning. Thus, gynecologists and oncologists are confronted more often with the question of childbearing after breast cancer. Current data from retrospective trials do not suggest an increased risk of a recurrence or progress of the disease associated with pregnancy after stage-adjusted treatment. Also, the risk of fetal malformations and damage to the fetus after chemotherapy and/or hormone therapy seems similar to that in the general population. Women who receive chemotherapy are advised to wait at least 6 months before they attempt to conceive. The question whether to become pregnant must be discussed individually with the patient, based on tumor characteristics, stage of the disease and patient's wishes.

Fertility and reproductive considerations in premenopausal patients with breast cancer

BACKGROUND

Approximately 10% of all new breast cancer diagnoses occur in young women. Although lacking medical comorbidities, these patients often have unique issues with regard to their reproductive health that merit special consideration. As breast cancer outcomes continue to improve, quality of life for patients and their families after breast cancer treatment has come to the forefront of cancer research, particularly in the growing field of oncofertility.

METHODS

This article reviews the literature on the singular situations and controversies faced by premenopausal breast cancer patients.

RESULTS

Data on amenorrhea and the effects of modern chemotherapeutic agents on amenorrhea are limited, although the role of tamoxifen in amenorrhea is more clearly defined as increasing the rate of amenorrhea across several studies. At the forefront of studies on fertility and premenopausal breast cancer patients are investigations on fertility preservation via ovarian protection and on assisted reproductive technologies. The use of gonadotropin-releasing hormone analogs for ovarian protection remains controversial and continues to be investigated.

CONCLUSIONS

Early integration of assessment and counseling regarding fertility preservation is part of the multidisciplinary approach in the care of the premenopausal breast cancer patient and is key to optimizing both cancer treatment and fertility plans for the future. Because of the many ongoing biological, practical, and ethical controversies surrounding oncofertility, eligible patients should be strongly encouraged to participate in clinical trials and studies to further increase our knowledge in this growing field.

Effect of childbirth after treatment on long-term survival from breast cancer

Background

This study quantified long-term absolute and relative mortality risks of survivors of breast cancer with subsequent childbirth.

Methods

The Singapore Birth Register (n = 319 437), Swedish Multi-Generation Register (n = 11 million) and population-based cancer registries were linked to identify 492 women with childbirth after breast cancer. For these women, cumulative mortality risks and standardized mortality ratios (SMRs) were calculated and compared with those of 8529 women aged less than 40 years with breast cancer without subsequent childbirth, and with those predicted by Adjuvant! Online.

Results

Women with subsequent childbirth had a lower 15-year cumulative overall mortality rate than other women with breast cancer (16·8 (95 per cent confidence interval (c.i.) 13·3 to 20·9) versus 40·7 (39·5 to 41·9) per cent), but a higher relative mortality risk than the background population (SMR 13·6, 95 per cent c.i. 10·6 to 17·3). Mortality risks decreased significantly with increasing interval between diagnosis and subsequent childbirth. Mean 10-year cumulative mortality risks of women with subsequent childbirth were within the range of 10-year mortality predicted by Adjuvant! Online for women with T1 N0 tumours in otherwise perfect health.

Conclusion

This study reinforced the view that pregnancy after breast cancer is not detrimental to survival. However, women who gave birth after this diagnosis had substantially higher mortality risks than young women in the general population. This information may be a valuable addition to routine mortality estimates.