Oral contraceptives and breast cancer risk in the international BRCA1/2 carrier cohort study: a report from EMBRACE, GENEPSO, GEO-HEBON, and the IBCCS Collaborating Group

Hormonal Contraception and Breast Cancer Risk for Carriers of Germline Mutations in BRCA1 and BRCA2

PURPOSE

It is uncertain whether, and to what extent, hormonal contraceptives increase breast cancer (BC) risk for germline BRCA1 or BRCA2 mutation carriers.

METHODS

Using pooled observational data from four prospective cohort studies, associations between hormonal contraceptive use and BC risk for unaffected female BRCA1 and BRCA2 mutation carriers were assessed using Cox regression.

RESULTS

Of 3,882 BRCA1 and 1,509 BRCA2 mutation carriers, 53% and 71%, respectively, had ever used hormonal contraceptives for at least 1 year (median cumulative duration of use, 4.8 and 5.7 years, respectively). Overall, 488 BRCA1 and 191 BRCA2 mutation carriers developed BC during median follow-up of 5.9 and 5.6 years, respectively. Although for BRCA1 mutation carriers, neither current nor past use of hormonal contraceptives for at least 1 year was statistically significantly associated with BC risk (hazard ratio [HR], 1.40 [95% CI, 0.94 to 2.08], P = .10 for current use; 1.16 [0.80 to 1.69], P = .4, 1.40 [0.99 to 1.97], P = .05, and 1.27 [0.98 to 1.63], P = .07 for past use 1-5, 6-10, and >10 years before, respectively), ever use was associated with increased risk (HR, 1.29 [95% CI, 1.04 to 1.60], P = .02). Furthermore, BC risk increased with longer cumulative duration of use, with an estimated proportional increase in risk of 3% (1%-5%, P = .002) for each additional year of use. For BRCA2 mutation carriers, there was no evidence that current or ever use was associated with increased BC risk (HR, 0.70 [95% CI, 0.33 to 1.47], P = .3 and 1.07 [0.73 to 1.57], P = .7, respectively).

CONCLUSION

Hormonal contraceptives were associated with increased BC risk for BRCA1 mutation carriers, especially if used for longer durations. Decisions about their use in women with BRCA1 mutations should carefully weigh the risks and benefits for each individual.

Assessing the impact of contraceptive use on reproductive cancer risk among women of reproductive age-a systematic review

Background

Contraceptives play a crucial role in women's reproductive health, their hormonal components may be linked to cancer risks, specifically breast, and gynecological cancers. Given the high usage rates of hormonal contraceptives, it is vital to systematically evaluate their potential impact on cancer outcomes, especially among women with a family history of gynecological cancers.

Objectives

This study aims to evaluate the evidence on the association between modern contraceptive use and the risk of breast and reproductive cancers (ovarian, endometrial, and cervical cancer) among women of reproductive age, to inform healthcare providers, women, and program managers about cancer outcomes related to contraceptive use.

Methods

A systematic review was conducted according to PRISMA guidelines. Searches were performed in databases such as CINAHL, OVID Medline, EMBASE, and more from inception to February 2022. Eligible studies included randomized controlled trials, cohort studies, and case-control studies that compared cancer outcomes between contraceptive users and non-users. Data extraction, quality assessment, and meta-analyses were conducted following predefined protocols. Subgroup and sensitivity analyses examined variations in contraceptive methods, doses, and duration.

Results

A total of 51 studies were included, comprising 2 RCTs and 49 observational studies. The review identified a significant reduction in ovarian and endometrial cancer incidence among contraceptive users. Hormonal contraceptive users had a 36% lower risk of ovarian cancer (RR 0.64, 95% CI 0.60-0.68), with specific reductions seen in combined oral contraceptive users (RR 0.62, 95% CI 0.57-0.68) and hormonal IUD users (RR 0.68, 95% CI 0.48-0.96). The rate ratio of cervical cancer was higher among non- users compared to hormonal contraceptive users when we pooled the results (1.28, 95% CI 1.21, 1.35). No significant association was found between contraceptive use and breast cancer risk among healthy women (RR 1.00, 95% CI 0.94-1.06). However, BRCA1/2 mutation carriers using oral contraceptives showed a heightened risk of breast cancer (HR 1.39, 95% CI 1.15-1.67).

Conclusion

This systematic review highlights the protective effects of modern contraceptives against ovarian and endometrial cancers while identifying an increased risk of cervical. No significant breast cancer risk was found for healthy women, but BRCA1/2 mutation carriers faced increased risks. These findings underscore the need for personalized contraceptive counselling that considers cancer risk factors. Further research is needed to explore contraceptive impacts across different genetic profiles and dosing regimens.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, Prospero (CRD42022332647).

U.S. Medical Eligibility Criteria for Contraceptive Use, 2024

The 2024 U.S. Medical Eligibility Criteria for Contraceptive Use (U.S. MEC) comprises recommendations for the use of specific contraceptive methods by persons who have certain characteristics or medical conditions. These recommendations for health care providers were updated by CDC after review of the scientific evidence and a meeting with national experts in Atlanta, Georgia, during January 25-27, 2023. The information in this report replaces the 2016 U.S. MEC (CDC. U.S. Medical Eligibility Criteria for Contraceptive Use, 2016. MMWR 2016:65[No. RR-3]:1-103). Notable updates include 1) the addition of recommendations for persons with chronic kidney disease; 2) revisions to the recommendations for persons with certain characteristics or medical conditions (i.e., breastfeeding, postpartum, postabortion, obesity, surgery, deep venous thrombosis or pulmonary embolism with or without anticoagulant therapy, thrombophilia, superficial venous thrombosis, valvular heart disease, peripartum cardiomyopathy, systemic lupus erythematosus, high risk for HIV infection, cirrhosis, liver tumor, sickle cell disease, solid organ transplantation, and drug interactions with antiretrovirals used for prevention or treatment of HIV infection); and 3) inclusion of new contraceptive methods, including new doses or formulations of combined oral contraceptives, contraceptive patches, vaginal rings, progestin-only pills, levonorgestrel intrauterine devices, and vaginal pH modulator. The recommendations in this report are intended to serve as a source of evidence-based clinical practice guidance for health care providers. The goals of these recommendations are to remove unnecessary medical barriers to accessing and using contraception and to support the provision of person-centered contraceptive counseling and services in a noncoercive manner. Health care providers should always consider the individual clinical circumstances of each person seeking contraceptive services. This report is not intended to be a substitute for professional medical advice for individual patients; when needed, patients should seek advice from their health care providers about contraceptive use.

Validation of the BOADICEA model in a prospective cohort of BRCA1/2 pathogenic variant carriers

BACKGROUND

No validation has been conducted for the BOADICEA multifactorial breast cancer risk prediction model specifically in BRCA1/2 pathogenic variant (PV) carriers to date. Here, we evaluated the performance of BOADICEA in predicting 5-year breast cancer risks in a prospective cohort of BRCA1/2 PV carriers ascertained through clinical genetic centres.

METHODS

We evaluated the model calibration and discriminatory ability in the prospective TRANsIBCCS cohort study comprising 1614 BRCA1 and 1365 BRCA2 PV carriers (209 incident cases). Study participants had lifestyle, reproductive, hormonal, anthropometric risk factor information, a polygenic risk score based on 313 SNPs and family history information.

RESULTS

The full multifactorial model considering family history together with all other risk factors was well calibrated overall (E/O=1.07, 95% CI: 0.92 to 1.24) and in quintiles of predicted risk. Discrimination was maximised when all risk factors were considered (Harrell's C-index=0.70, 95% CI: 0.67 to 0.74; area under the curve=0.79, 95% CI: 0.76 to 0.82). The model performance was similar when evaluated separately in BRCA1 or BRCA2 PV carriers. The full model identified 5.8%, 12.9% and 24.0% of BRCA1/2 PV carriers with 5-year breast cancer risks of <1.65%, <3% and <5%, respectively, risk thresholds commonly used for different management and risk-reduction options.

CONCLUSION

BOADICEA may be used to aid personalised cancer risk management and decision-making for BRCA1 and BRCA2 PV carriers. It is implemented in the free-access CanRisk tool (https://www.canrisk.org/).

Age-specific breast and ovarian cancer risks associated with germline BRCA1 or BRCA2 pathogenic variants - an Asian study of 572 families

Background

Clinical management of Asian BRCA1 and BRCA2 pathogenic variants (PV) carriers remains challenging due to imprecise age-specific breast (BC) and ovarian cancer (OC) risks estimates. We aimed to refine these estimates using six multi-ethnic studies in Asia.

Methods

Data were collected on 271 BRCA1 and 301 BRCA2 families from Malaysia and Singapore, ascertained through population/hospital-based case-series (88%) and genetic clinics (12%). Age-specific cancer risks were estimated using a modified segregation analysis method, adjusted for ascertainment.

Findings

BC and OC relative risks (RRs) varied across age groups for both BRCA1 and BRCA2. The age-specific RR estimates were similar across ethnicities and country of residence. For BRCA1 carriers of Malay, Indian and Chinese ancestry born between 1950 and 1959 in Malaysia, the cumulative risk (95% CI) of BC by age 80 was 40% (36%-44%), 49% (44%-53%) and 55% (51%-60%), respectively. The corresponding estimates for BRCA2 were 29% (26-32%), 36% (33%-40%) and 42% (38%-45%). The corresponding cumulative BC risks for Singapore residents from the same birth cohort, where the underlying population cancer incidences are higher compared to Malaysia, were higher, varying by ancestry group between 57 and 61% for BRCA1, and between 43 and 47% for BRCA2 carriers. The cumulative risk of OC by age 80 was 31% (27-36%) for BRCA1 and 12% (10%-15%) for BRCA2 carriers in Malaysia born between 1950 and 1959; and 42% (34-50%) for BRCA1 and 20% (14-27%) for BRCA2 carriers of the same birth cohort in Singapore. There was evidence of increased BC and OC risks for women from >1960 birth cohorts (p-value = 3.6 × 10-5 for BRCA1 and 0.018 for BRCA2).

Interpretation

The absolute age-specific cancer risks of Asian carriers vary depending on the underlying population-specific cancer incidences, and hence should be customised to allow for more accurate cancer risk management.

Funding

Wellcome Trust [grant no: v203477/Z/16/Z]; CRUK (PPRPGM-Nov20∖100002).

Modifiable risk factors in women at high risk of breast cancer: a systematic review

BACKGROUND

Modifiable risk factors (alcohol, smoking, obesity, hormone use, and physical activity) affect a woman's breast cancer (BC) risk. Whether these factors affect BC risk in women with inherited risk (family history, BRCA1/2 mutations, or familial cancer syndrome) remains unclear.

METHODS

This review included studies on modifiable risk factors for BC in women with inherited risk. Pre-determined eligibility criteria were used and relevant data were extracted.

RESULTS

The literature search resulted in 93 eligible studies. For women with family history, most studies indicated that modifiable risk factors had no association with BC and some indicated decreased (physical activity) or increased risk (hormonal contraception (HC)/menopausal hormone therapy (MHT), smoking, alcohol). For women with BRCA mutations, most studies reported no association between modifiable risk factors and BC; however, some observed increased (smoking, MHT/HC, body mass index (BMI)/weight) and decreased risk (alcohol, smoking, MHT/HC, BMI/weight, physical activity). However, measurements varied widely among studies, sample sizes were often small, and a limited number of studies existed.

CONCLUSIONS

An increasing number of women will recognize their underlying inherited BC risk and seek to modify that risk. Due to heterogeneity and limited power of existing studies, further studies are needed to better understand how modifiable risk factors influence BC risk in women with inherited risk.

Contraceptives and cancer risks in BRCA1/2 pathogenic variant carriers: a systematic review and meta-analysis

BACKGROUND

Increasing numbers of BReast CAncer (BRCA) 1 or 2 pathogenic variant (PV) carriers, who have an inherited predisposition to breast and ovarian cancer, are being identified. Among these women, data regarding the effects of contraception on cancer risks are unclear and various guidelines provide various recommendations.

OBJECTIVE AND RATIONALE

We aim to optimize counselling regarding contraception for BRCA1/2-PV carriers. Therefore, we performed a systematic review and meta-analysis. We investigated the risk ratio for developing breast cancer or ovarian cancer in BRCA1/2-PV carriers who have used any form of contraception versus non-users. Second, we analysed breast and ovarian cancer risk among BRCA1/2-PV carriers as influenced by the duration of contraceptive use and by the time since last use. In addition, we provide an overview of all relevant international guidelines regarding contraceptive use for BRCA1/2-PV carriers.

SEARCH METHODS

A systematic search in the Medline database and Cochrane library identified studies describing breast and/or ovarian cancer risk in BRCA1/2-PV carriers as modified by contraception until June 2021. The search included medical subject headings, keywords and synonyms related to BRCA and contraceptives (any kind). PRISMA guidance was followed. Risk Of Bias In Non-randomized Studies of Interventions and Grading of Recommendations, Assessment, Development and Evaluations assessments were performed. Random-effects meta-analyses were used to estimate pooled effects for breast and ovarian cancer risk separately. Subgroup analyses were conducted for BRCA1 versus BRCA2 and for the various contraceptive methods.

OUTCOMES

Results of the breast cancer risk with oral contraceptive pill (OCP) analysis depended on the outcome measure. Meta-analyses of seven studies with 7525 women revealed a hazard ratio (HR) of 1.55 (95% CI: 1.36-1.76) and of four studies including 9106 women resulted in an odds ratio (OR) of 1.06 (95% CI: 0.90-1.25), heterogeneity (I2) 0% and 52%, respectively. Breast cancer risk was still increased in ever-users compared with never-users >10 years after last OCP use. In contrast, ovarian cancer risk was decreased among OCP users: HR 0.62 (95% CI: 0.52-0.74) based on two studies including 10 981 women (I2: 0%), and OR 0.49 (95% CI: 0.38-0.63) based on eight studies including 10 390 women (I2: 64%). The protective effect vanished after cessation of use. Tubal ligation also protects against ovarian cancer: one study including 3319 women (I2: 0%): HR: 0.44 (95% CI: 0.26-0.74) and three studies with 7691 women (I2: 44%): OR: 0.74 (95% CI: 0.53-1.03). Data regarding other contraceptives were unavailable. No differences were observed between BRCA1 and BRCA2-PV carriers. The quality of evidence was either low or very low.

WIDER IMPLICATIONS

The OCP potentially increases breast cancer risk, while ovarian cancer risk decreases with either the OCP and tubal ligation in BRCA1/2-PV carriers. Counselling of BRCA1/2-PV carriers should be personalized; the genetic and non-genetic factors (like prior risk-reducing surgeries, prior breast cancer and age) and patients' preferences (reversibility, ease of use, reliability and effect on menstrual cycle) should be balanced. To further optimize counselling for high-risk women, future research should focus on other (commonly used) contraceptive methods and cancer risks in this specific population, and on the potential impact of changing formulations over time.

Prospective validation of the BOADICEA multifactorial breast cancer risk prediction model in a large prospective cohort study

BACKGROUND

The multifactorial Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) breast cancer risk prediction model has been recently extended to consider all established breast cancer risk factors. We assessed the clinical validity of the model in a large independent prospective cohort.

METHODS

We validated BOADICEA (V.6) in the Swedish KARolinska Mammography Project for Risk Prediction of Breast Cancer (KARMA) cohort including 66 415 women of European ancestry (median age 54 years, IQR 45-63; 816 incident breast cancers) without previous cancer diagnosis. We calculated 5-year risks on the basis of questionnaire-based risk factors, pedigree-structured first-degree family history, mammographic density (BI-RADS), a validated breast cancer polygenic risk score (PRS) based on 313-SNPs, and pathogenic variant status in 8 breast cancer susceptibility genes: BRCA1, BRCA2, PALB2, CHEK2, ATM, RAD51C, RAD51D and BARD1. Calibration was assessed by comparing observed and expected risks in deciles of predicted risk and the calibration slope. The discriminatory ability was assessed using the area under the curve (AUC).

RESULTS

Among the individual model components, the PRS contributed most to breast cancer risk stratification. BOADICEA was well calibrated in predicting the risks for low-risk and high-risk women when all, or subsets of risk factors are included in the risk prediction. Discrimination was maximised when all risk factors are considered (AUC=0.70, 95% CI: 0.66 to 0.73; expected-to-observed ratio=0.88, 95% CI: 0.75 to 1.04; calibration slope=0.97, 95% CI: 0.95 to 0.99). The full multifactorial model classified 3.6% women as high risk (5-year risk ≥3%) and 11.1% as very low risk (5-year risk <0.33%).

CONCLUSION

The multifactorial BOADICEA model provides valid breast cancer risk predictions and a basis for personalised decision-making on disease prevention and screening.

Oral Contraceptive Use and Breast Cancer Risk for BRCA1 and BRCA2 Mutation Carriers: Systematic Review and Meta-Analysis of Case–Control Studies

Oral contraceptive use is one of the major modifiable risk factors for breast cancer. To investigate the effect of oral contraceptive taking on breast cancer risk by BRCA 1 and BRCA 2 mutation status, we conducted a systematic review and meta-analysis of case-controlled studies. Therefore, English language articles were retrieved by searching MEDLINE (PubMed), EMBASE and the Cochrane Library up to August 2021. Data were pooled from none case–control studies, comprising a total of 33,162 subjects, including 23,453 who had never used oral contraceptives. Overall meta-analysis indicated a statistically insignificant risk reduction: OR = 0.86, 95% CI: 0.70 to 1.06, p = 0.1594. However, increased breast cancer risk was associated with age at first use of OCs ≥20 years: OR = 1.21, 95% CI:1.07 to 1.36, p = 0.002. Multivariable meta-regression with covariates of age of first OC use (β = 0.21, 95% CI: −0.25 to 0.67, p = 0.3767), duration of OC use (β = −0.08, 95% CI; −0.51 to 0.34, p = 0.7093), and time since last OC use (β = 0.32, 95% CI: −0.22 to 0.85, p = 0.2461) did not have a significant effect on the breast cancer risk. This meta-analysis suggests a diverse effect of oral contraceptive use against breast cancer in BRCA carrier mutation. The association between OC use and breast and ovarian cancers needs more investigation.

BRCA mutation carriers' perception about benefits and risks associated with combined hormonal contraceptives use

OBJECTIVE

To evaluate the actual perceptions about combined hormonal contraceptives (CHCs) use in BRCA mutation carriers in comparison to women from the general population.

METHODS

This was a cross-sectional, observational study involving two Italian referral centres for hereditary cancers. An identical questionnaire investigating how CHC use could affect the risk of developing some types of cancer, specific diseases, and symptoms was administered to 85 BRCA mutation carriers and 85 healthy women without this genetic mutation (control group). Women's perceptions were evaluated using specific questions and Likert scales (-5 to +5).

RESULTS

Perceptions about the effects of CHC use on developing specific diseases and symptoms did not differ between BRCA mutation carriers and controls. Conversely, the protective effects of CHC use on colorectal (p = .02), uterine body (p = .01) and ovarian (p = .01) cancers were unknown by BRCA mutation carriers. Moreover, BRCA mutation carriers recognised the association between CHC use and a higher risk of breast (p = .0008) and uterine cervix cancer (p = .007).

CONCLUSIONS

Investing time and effort in transmitting the correct key messages about oncological risk related to CHC use could potentially increase their use in BRCA mutation carriers.

Exogenous Hormones and Breast Cancer Risk: Contraception, Menopausal Hormone Therapy, and Breast Cancer Survivors

The use of exogenous estrogen and progesterone/progestin medications spans the reproductive and postreproductive lives of millions of women providing control over pregnancy timing, management of premenopausal and postmenopausal symptoms, and prevention of disease, including endometrial and ovarian cancer. These same hormones can also increase the risk of breast cancer in some settings and their use in breast cancer survivors may increase the risk of breast cancer recurrence. Given both the benefits and risks of these exogenous hormones, a detailed understanding of the available scientific evidence is imperative to help counsel individuals in their use across various settings.

Oral contraceptives and risk of breast cancer and ovarian cancer in women with a BRCA1 or BRCA2 mutation: A meta-analysis of observational studies

It remains inconclusive whether the use of oral contraceptives (OCs) alters the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. We investigated the association between OC use and the risks of breast or ovarian cancer in this group by using a meta-analysis. PubMed and EMBASE were searched using keywords until February 2021 to identify relevant studies that evaluated the association between OC ever use and the risks of breast or ovarian cancer in women with a BRCA1 or BRCA2 mutation. Twelve studies for breast cancer and eight studies for ovarian cancer were identified. In the random-effects meta-analysis, the ever use of OCs was significantly associated with an increased risk of breast cancer [odds ratio (OR), relative risk (RR), or hazard ration (HR) = 1.24; 95% confidence interval (CI) 1.08 - 1.41] and a decreased risk of ovarian cancer (OR/RR/HR = 0.53, 95% CI 0.41 - 0.67). Consistent findings were observed, when BRCA1 and BRCA2 mutation carriers were analyzed separately. The increased risk of breast cancer was observed only in the long-term (>5 years) users of OCs, while the decrease risk of ovarian cancer was observed regardless of the duration of OC use. The current study suggests that the ever use of OCs in BRCA mutation carriers is significantly associated with an increased risk of breast cancer and a decreased risk of ovarian cancer. Therefore, the use of OCs as chemoprevention of ovarian cancer should be cautious in BRCA mutation carriers.

Use of Oral Contraceptives as a Potential Risk Factor for Breast Cancer: A Systematic Review and Meta-Analysis of Case-Control Studies Up to 2010

Despite numerous studies evaluating the risk of breast cancer among oral contraception users, the effect of oral contraceptive on developing breast cancer remains inconclusive. Therefore, we conducted a systematic review of literature with meta-analysis in order to quantitative estimate this association. The bibliographic database MEDLINE and EMBASE, and reference lists of identified articles were searched, with no language restrictions, from the start of publication to August 2010. We performed a reanalysis and overall estimate of 79 case-control studies conducted between 1960-2010, including a total of 72,030 incidents, histologically confirmed cases of breast cancer and 123,650 population/hospital controls. A decrease was observed in cancer risk in OC users before age 25 years (0.91, 0.83-1.00). However, the use of OCs before the first full-term pregnancy had a significant increased risk of breast cancer (OR, 1.14, 1.01-1.28, p = 0.04), as did OC use longer than 5 years (1.09, 1.01-1.18, p = 0.02). Pooled crude odds ratios of breast cancer in ever-users of oral contraceptives was 1.01 [95% confidence interval (CI), 0.95-1.07], compared with never-users. There was no significant increase in risk among premenopausal women (1.06, 0.92-1.22), postmenopausal women (0.99, 0.89-1.10), or nulliparous women (1.02, 0.82-1.26). Oral contraceptives do not appear to increase the risk of breast cancer among users. However, OC use before a first full-term pregnancy or using them longer than 5 years can modify the development of the breast cancer.

Use of oral contraceptives in BRCA mutation carriers and risk for ovarian and breast cancer: a systematic review

PURPOSE

BRCA mutation carriers have an increased risk of developing breast or ovarian cancer. Oral contraception (OC) is known to increase breast cancer and reduce ovarian cancer risk in the general population. This review analyses the published data on OC and risk of cancer in BRCA mutation carriers.

METHODS

We included all relevant articles published in English from 1995 to 2018. Literature was identified through a search on PubMed and Cochrane Library.

RESULTS

We included four meta-analyses, one review, one case-control study and one retrospective cohort study on the association between ovarian cancer and OC in BRCA mutation carriers. All report a risk reduction for the OC users and several also describe an inverse correlation with duration of use. Regarding breast cancer, we included four meta-analyses, one review, one case-control study, two case-only studies, one prospective and one retrospective cohort study. Some studies report a risk elevation, while others did not find an association between OC use and breast cancer in BRCA mutation carriers. In other studies, the association was limited to early-onset breast cancer and/or associated with young age at first start of OC.

CONCLUSION

Oral contraception leads to a risk reduction of ovarian cancer also in BRCA mutation carriers. An increase in breast cancer risk due to OC cannot be excluded. Women with BRCA mutation who consider OC use have to be informed about possible increase in breast cancer risk and alternative contraceptive methods. OC should not be used for the prevention of ovarian cancer in this population.

No. 329-Canadian Contraception Consensus Part 4 of 4 Chapter 9: Combined Hormonal Contraception

OBJECTIVE

To provide guidelines for health care providers on the use of contraceptive methods to prevent pregnancy and on the promotion of healthy sexuality.

OUTCOMES

Overall efficacy of cited contraceptive methods, assessing reduction in pregnancy rate, safety, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the availability of cited contraceptive methods in Canada.

EVIDENCE

Medline and the Cochrane Database were searched for articles in English on subjects related to contraception, sexuality, and sexual health from January 1994 to December 2015 in order to update the Canadian Contraception Consensus published February-April 2004. Relevant Canadian government publications and position papers from appropriate health and family planning organizations were also reviewed.

VALUES

The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice are ranked according to the method described in this report.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Association of Combined Estrogen-Progestogen and Progestogen-Only Contraceptives with the Development of Cancer

Combined estrogen-progestogen contraceptives (oral contraceptives or OCs) and progestogen-only contraceptives (POCs) are synthetic steroids that bind to steroid hormone receptors, which are widespread throughout the body. They have a profound effect on cellular physiology. Combined OCs have been classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogens, but their findings have not been updated recently. In order to update the information and better understand the impact that OCs and POCs have on the risk of development of cancers, a comprehensive literature search was undertaken, focusing on more recently published papers. In agreement with the IARC, the recent literature confirms an increased risk of breast cancer and cervical cancer with the use of OCs. The recent literature also confirms the IARC conclusion that OCs decrease the risk of ovarian and endometrial cancers. However, there is little support from recent studies for the IARC conclusion that OCs decrease the risk of colorectal cancer or increase the risk of liver cancer. For liver cancer, this may be due to the recent studies having been performed in areas where hepatitis is endemic. In one large observational study, POCs also appear to increase the overall risk of developing cancer. OCs and POCs appear to increase the overall risk of cancer when carefully performed studies with the least intrinsic bias are considered.

Summary

OCs have been classified as cancer-causing agents, especially leading to increases in breast cancer and cervical cancer. A review of the recent scientific literature was performed to see whether this still appears to be the case. The recent literature supports the cancer-causing role of OCs especially for breast cancer and cervical cancer. Studies also indicate that progesterone-only contraceptives (such as implants and vaginal rings) also can cause cancer. This is especially true for breast cancer and cervical cancer.

Reducing the Risk of Gynecologic Cancer in Hereditary Breast Ovarian Cancer Syndrome Mutation Carriers: Moral Dilemmas and the Principle of Double Effect

Hereditary breast ovarian cancer (HBOC) syndrome is an autosomal dominant disease linked to mutations in the BRCA1 and BRCA2 genes in 90 percent of affected families. Female mutation carriers are highly susceptible to aggressive, often disseminated, usually fatal pelvic-abdominal carcinomatosis. This cancer risk can be markedly reduced by surgical removal of the internal gynecologic organs before the end of the fourth decade of life and by using estrogen-progestin formulations marketed for many years as combined oral contraceptives (COCs). Both risk-reducing methods are associated with unfavorable effects. Relying on the principle of double effect, this essay argues for the ethical justification of prophylactic surgery and the use of COC to reduce the risk of gynecologic cancer in HBOC syndrome mutation carriers. Summary: Hereditary breast ovarian cancer syndrome is an autosomal dominant disease linked to mutations in the BRCA1 and BRCA2 genes in most affected families. Female mutation carriers are highly susceptible to aggressive, often disseminated, usually fatal pelvic-abdominal carcinomatosis. This cancer risk can be markedly reduced by surgical removal of the internal gynecologic organs before the end of the fourth decade of life and by using estrogen-progestin formulations marketed for many years as combined oral contraceptives. Both risk-reducing methods are associated with unfavorable effects. Relying on the principle of double effect, this essay argues for the ethical justification for those unfavorable effects.

Oral Contraceptive Use and Breast Cancer Risk: Retrospective and Prospective Analyses From a BRCA1 and BRCA2 Mutation Carrier Cohort Study

BACKGROUND

For BRCA1 and BRCA2 mutation carriers, the association between oral contraceptive preparation (OCP) use and breast cancer (BC) risk is still unclear.

METHODS

Breast camcer risk associations were estimated from OCP data on 6030 BRCA1 and 3809 BRCA2 mutation carriers using age-dependent Cox regression, stratified by study and birth cohort. Prospective, left-truncated retrospective and full-cohort retrospective analyses were performed.

RESULTS

For BRCA1 mutation carriers, OCP use was not associated with BC risk in prospective analyses (hazard ratio [HR] = 1.08, 95% confidence interval [CI] = 0.75 to 1.56), but in the left-truncated and full-cohort retrospective analyses, risks were increased by 26% (95% CI = 6% to 51%) and 39% (95% CI = 23% to 58%), respectively. For BRCA2 mutation carriers, OCP use was associated with BC risk in prospective analyses (HR = 1.75, 95% CI = 1.03 to 2.97), but retrospective analyses were inconsistent (left-truncated: HR = 1.06, 95% CI = 0.85 to 1.33; full cohort: HR = 1.52, 95% CI = 1.28 to 1.81). There was evidence of increasing risk with duration of use, especially before the first full-term pregnancy (BRCA1: both retrospective analyses, P < .001 and P = .001, respectively; BRCA2: full retrospective analysis, P = .002).

CONCLUSIONS

Prospective analyses did not show that past use of OCP is associated with an increased BC risk for BRCA1 mutation carriers in young middle-aged women (40-50 years). For BRCA2 mutation carriers, a causal association is also not likely at those ages. Findings between retrospective and prospective analyses were inconsistent and could be due to survival bias or a true association for younger women who were underrepresented in the prospective cohort. Given the uncertain safety of long-term OCP use for BRCA1/2 mutation carriers, indications other than contraception should be avoided and nonhormonal contraceptive methods should be discussed.

Hormonal contraceptives and breast cancer: Clinical data

The endocrine background of breast cancer has raised questions about the increase in risk that might bear the use of hormonal contraceptives. This has been a particular issue in the case of young women, who constitute the population of contraceptive consumers. Observational studies have been the main source of evidence, which has mainly limited to the combined estrogen-progestogen preparations, the popular pill. Studies in the 80's and 90's of the past century found a small, around a 20%, increase in risk. The translation in absolute number of excess cases has been exiguous because the prevalence of the disease is relatively small in premenopausal women. Moreover, the risk slowly seemed to disappear after 5-10 years of use. The more sophisticated analyses provided by new technologies, together with the powerful central registries in some countries, has confirmed increased risk of similar size. Recent preparations, with lower doses of estrogens and new progestogenic molecules, have not substantially modified the risk size. The impact of progestogen only alternatives, either pills or progestogen-loaded intrauterine devices, seems to be similar, but the evidence is still insufficient. Whether there is a preferential effect on histological or molecular subtypes of breast tumours is being debated yet. The data on women at higher risk, either with mutations of the BRCA1/2 genes or with familial weight, have not found specific response patterns, but the experience is still meagre. It is of interest that long-term follow up data on women who enrolled in the initial cohorts, like that of the Royal College of General Practitioners', have shown a considerable protection against cancer of the ovary (relative risk, RR 0.67), endometrium (RR 0.66), or colorectum (RR 0.81).

Proliferation and ovarian hormone signaling are impaired in normal breast tissues from women with BRCA1 mutations: benefit of a progesterone receptor modulator treatment as a breast cancer preventive strategy in women with inherited BRCA1 mutations

Women with inherited BRCA1 mutations have an elevated risk (40-80%) for developing breast and ovarian cancers. Reproductive history has been reported to alter this risk, suggesting a relationship between ovarian hormone signaling and BRCA1-related tumor development. BRCA1 interactions with estrogen receptor (ER) and progesterone receptor (PR) signaling were previously described in human breast cancer cell lines and mouse models. However, few studies have examined the effect of ovarian hormone regulation in normal human breast tissues bearing a heterozygous BRCA1 mutation. This study compares the proliferation level (Ki67) and the expression of ER, PR, and of the PR target gene, fatty acid synthase (FASN), in histologically normal breast tissues from women with BRCA1 mutations (BRCA1+/mut, n=23) or without BRCA1 mutations (BRCA1+/+, n=28). BRCA1+/mut tissues showed an increased proliferation and impaired hormone receptor expression with a marked loss of the PR isoform, PR-B. Responses to estradiol and progesterone treatments in BRCA1+/mut and BRCA1+/+ breast tissues were studied in a mouse xenograft model, and showed that PR and FASN expression were deregulated in BRCA1+/mut breast tissues. Progesterone added to estradiol treatment increased the proliferation in a subset of BRCA1+/mut breast tissues. The PR inhibitor, ulipristal acetate (UPA), was able to reverse this aberrant progesterone-induced proliferation. This study suggests that a subset of women with BRCA1 mutations could be candidates for a UPA treatment as a preventive breast cancer strategy.

Combined Hormonal Contraceptive Use and Risk of Breast Cancer in a Population of Women With a Family History

BACKGROUND

We estimated the association between combined hormonal contraceptive (CHC) use and breast cancer (BC) incidence in a well-selected population of women at familial risk of BC at the Modena Family Cancer Clinic.

MATERIALS AND METHODS

We performed a retrospective cohort study by reviewing the data from 2527 women (4.5% BRCA mutation carriers, 72.2% high risk, and 23.3% intermediate risk using the Modena criteria and the Tyrer-Cuzick model).

RESULTS

We did not find any specific feature of breast cancer (infiltration, hormone receptor and HER2 status, onset before age 35 years, multiple diagnoses) in the CHC users (P > .05). Only 2.0% of women used a preparation with ≥ 50 μg of ethinylestradiol (EE). The use of CHCs was not associated with an increased risk of breast cancer (cumulative hazard: never used, 0.17; CHC users, 0.20; P = .998), regardless of the duration of use (cumulative hazard: never used, 0.17, used < 5 years, 0.20; used 5-10 years, 0.14; used > 10 years, 0.25; P = .414). This was confirmed for the different risk groups when interacted in a Cox proportional hazard regression model. The EE dose did not influence the risk of BC (cumulative hazard, 2.37; 95% confidence interval, 0.53-10.1; never used, 0.18; EE < 20 μg used, 0.04; EE ≥ 20 μg used, 0.16; P = .259). The types of progestins used might influence the risk, with some, such as gestodene (P = .028) and cyproterone acetate (P = .031), associated with an even greater reduced risk.

CONCLUSIONS

CHC use does not increase the risk of BC in a population of women with a family history, encouraging CHC use in this group of women.

Missed therapeutic and prevention opportunities in women with BRCA-mutated epithelial ovarian cancer and their families due to low referral rates for genetic counseling and BRCA testing: A review of the literature

Answer questions and earn CME/CNE Fifteen percent of women with epithelial ovarian cancer have inherited mutations in the BRCA breast cancer susceptibility genes. Knowledge of her BRCA status has value both for the woman and for her family. A therapeutic benefit exists for the woman with cancer, because a new family of oral drugs, the poly ADP-ribose polymerase (PARP) inhibitors, has recently been approved, and these drugs have the greatest efficacy in women who carry the mutation. For her family, there is the potential to prevent ovarian cancer in those carrying the mutation by using risk-reducing surgery. Such surgery significantly reduces the chance of developing this, for the most part, incurable cancer. Despite these potential benefits, referral rates for genetic counseling and subsequent BRCA testing are low, ranging from 10% to 30%, indicating that these therapeutic and prevention opportunities are being missed. The authors have reviewed the relevant available literature. Topics discussed are BRCA and its relation to ovarian cancer, the rates of referral for genetic counseling/BRCA testing, reasons for these low rates, potential strategies to improve on those rates, lack of effectiveness of current screening strategies, the pros and cons of risk-reducing surgery, other prevention options, and the role and value of PARP inhibitors. CA Cancer J Clin 2017;67:493-506. © 2017 American Cancer Society.

Modifiers of breast and ovarian cancer risks for BRCA1 and BRCA2 mutation carriers

Pathogenic mutations in BRCA1 and BRCA2 are associated with high risks of breast and ovarian cancer. However, penetrance estimates for mutation carriers have been found to vary substantially between studies, and the observed differences in risk are consistent with the hypothesis that genetic and environmental factors modify cancer risks for women with these mutations. Direct evidence that this is the case has emerged in the past decade, through large-scale international collaborative efforts. Here, we describe the methodological challenges in the identification and characterisation of these risk-modifying factors, review the latest evidence on genetic and lifestyle/hormonal risk factors that modify breast and ovarian cancer risks for women with BRCA1 and BRCA2 mutations and outline the implications of these findings for cancer risk prediction. We also review the unresolved issues in this area of research and identify strategies of clinical implementation so that women with BRCA1 and BRCA2 mutations are no longer counselled on the basis of 'average' risk estimates.

Genetic testing for hereditary cancer predisposition: BRCA1/2, Lynch syndrome, and beyond

Obstetrician/gynecologists and gynecologic oncologists serve an integral role in the care of women at increased hereditary risk of cancer. Their contribution includes initial identification of high risk patients, screening procedures like bimanual exam, trans-vaginal ultrasound and endometrial biopsy, prophylaxis via TAH and/or BSO, and chemoprevention. Further, gynecologists also serve a central role in the management of the secondary repercussions of efforts to mitigate increased cancer risks, including vasomotor symptoms, sexual function, bone health, cardiovascular disease, and mental health. The past several years has seen multiple new high and moderate penetrance genes introduced into the clinical care of women at increased risk of gynecologic malignancy. Awareness of these new genes and the availability of new multi-gene panel tests is critical for providers on the front-line of women's health.

Gene-environment interaction and risk of breast cancer

Hereditary, genetic factors as well as lifestyle and environmental factors, for example, parity and body mass index, predict breast cancer development. Gene-environment interaction studies may help to identify subgroups of women at high-risk of breast cancer and can be leveraged to discover new genetic risk factors. A few interesting results in studies including over 30,000 breast cancer cases and healthy controls indicate that such interactions exist. Explorative gene-environment interaction studies aiming to identify new genetic or environmental factors are scarce and still underpowered. Gene-environment interactions might be stronger for rare genetic variants, but data are lacking. Ongoing initiatives to genotype larger sample sets in combination with comprehensive epidemiologic databases will provide further opportunities to study gene-environment interactions in breast cancer. However, based on the available evidence, we conclude that associations between the common genetic variants known today and breast cancer risk are only weakly modified by environmental factors, if at all.

Effect of lifestyle and reproductive factors on the onset of breast cancer in female BRCA 1 and 2 mutation carriers

BACKGROUND

The birth year-dependent onset of breast cancer (BC) in BRCA1/2 mutation carriers suggests a risk-modifying role for reproductive and life style factors. We therefore examined possible associations between these factors and age at diagnosis.

METHODS

Cox regression analysis and log-Rank testing were used to estimate the effect of potential life style factors on the onset of BC in 197 BRCA mutation carriers.

RESULTS

Nulliparous BRCA mutation carriers developed BC earlier than those who had delivered (36.4 vs. 40.9; P = 0.001). Similarly, smokers and women who had used oral contraceptives experienced an earlier cancer onset (39.0 vs. 41.4; P = 0.05 and 39.3 vs. 44.9; P = 0.0001, respectively). In multivariate analysis, oral contraceptive use (HR: 1.7; P = 0.006) and birth cohort (< vs. ≥1965 HR: 4.5; P = 0.001) were associated with an earlier BC onset, while previous pregnancies led to a delay (HR: 0.2; P = 0.04). Mutation carriers born ≥1965 were less likely to have experienced pregnancies and more likely to have used oral contraceptives, and consequently developed BC at an earlier age (median age: 42 vs. 58; P < 0.0001 log-Rank test).

CONCLUSION

We here demonstrate that in BRCA1/2 mutation carriers the birth cohort-associated differences in the onset of BC are profound and influenced by reproductive factors.

Breast Cancer Risk Associated with Estrogen Exposure and Truncating Mutation Location in BRCA1/2 Carriers

BACKGROUND

Mutations in BRCA1/2 confer a high risk of breast cancer, but literature values of this risk vary. A genotype-phenotype correlation has been found in both genes, and the effect of reproductive factors differs according to mutation location. Therefore, we hypothesize that such a variation may exist for other factors related to estrogen exposure.

METHODS

We used a weighted Cox regression model to assess variation in breast cancer risk with these factors using location of mutation in homogeneous breast cancer risk region of BRCA1/2 in the GENEPSO study.

RESULTS

We found that late age at menarche reduced breast cancer risk by 31% and that among BRCA1 carriers, a long or a short menstrual cycle increased risk (by 65% and 73%, respectively). Among premenopausal women, overweight was associated with a 45% decrease in risk whereas underweight was associated with an increased risk (HR, 2.40). A natural menopause, mainly after age 50, was associated with a high breast cancer risk (HR, 2.46), and a significant interaction between menopause status and the location of mutations was found leading up to 10% variation in absolute risk according to the age at menopause.

CONCLUSIONS

As observed in the general population, a late menarche, a long or a short menstrual cycle, over- or underweight, and being postmenopausal were associated with breast cancer risk in BRCA1/2 carriers. The association with the menopause was observed only when the mutation was located in the "high-risk" zones.

IMPACT

Taking into account modifier factors, location of mutation might be important for the clinical management of BRCA1/2 mutation carriers.

Risk-benefit assessment of the combined oral contraceptive pill in women with a family history of female cancer

INTRODUCTION

Oral contraceptive pills (OCPs) are the most frequently used form of effective, reversible contraception among women of childbearing potential. In the average risk population, OCPs may offer a protective benefit against ovarian, endometrial and colorectal malignancies. In women at high risk for breast, ovarian, endometrial or colorectal malignancies, the risk-benefit profile is less well studied.

AREAS COVERED

In this article, we review pertinent literature on the use of OCPs in patients with genetic susceptibilities due to mutations in BRCA1, BRCA2 or mismatch repair genes implicated in hereditary nonpolyposis colorectal cancer as well as those with a strong family history of malignancies associated with these syndromes.

EXPERT OPINION

For women at high risk for ovarian, endometrial and/or colorectal malignancies due to genetic susceptibilities or a strong family history, the possibility of chemoprevention with OCPs may be an attractive option; however, the potential increase in breast cancer, although small, must be considered in clinical decision-making. The ultimate decision to use OCPs in a high-risk woman should be based on a consideration of her specific genetic risk, her age, her reproductive plans and her willingness to consider surgical prophylaxis options.

Modifiers of cancer risk in BRCA1 and BRCA2 mutation carriers: systematic review and meta-analysis

BACKGROUND

There is substantial variability in cancer risk in women who have inherited a BRCA1 or BRCA2 (BRCA1/2) mutation. Numerous factors have been hypothesized to modify these risks, but studies are of variable quality, and it remains unclear which of these may be of value in clinical risk assessment.

METHODS

PubMed and Web of Science databases were searched for articles published through September 2013. Fixed effects meta-analysis was done using the hazard ratios and/or odds ratios to estimate the pooled effect estimates (ES) and 95% confidence intervals (CIs) to identify factors that are associated with cancer risk modification in BRCA1/2 mutation carriers.

RESULTS

We identified 44 nonoverlapping studies that met predefined quality criteria. Sufficient evidence is available to make clinically relevant inferences about a number of cancer risk modifiers. The only variable examined that produced a probable association was late age at first live birth, a meta-analysis showed a decrease in the risk of breast cancer in BRCA1 mutation carriers with women aged 30 years or older vs. women younger than 30 years (ES = 0.65; 95% CI =0.42 to 0.99). The same was shown for women aged 25 to 29 years versus those aged less than 25 years (ES = 0.69; 95% CI = 0.48 to 0.99). Breastfeeding and tubal ligation were associated with reduced ovarian cancer risk in BRCA1 mutation carriers; oral contraceptives were associated with reduced risk among BRCA1/2 mutation carriers. Smoking was associated with increased breast cancer risk in BRCA2 mutation carriers only.

CONCLUSIONS

Data assessing many potential risk modifiers are inadequate, and many have not been externally validated. Although additional studies are required to confirm some associations, sufficient information is available for some risk factors to be used in risk counseling or lifestyle modification to minimize cancer risk in BRCA1/2 mutation carriers

Acceptability of chemoprevention trials in high-risk subjects

The development and current widespread acceptance of clinical trials is one of the major conceptual advances in research medicine introduced during the second half of the 20th century. Despite general agreement on the scientific merits of randomization, many patients and physicians are however reluctant to participate in randomized, controlled trials. If we focus on chemoprevention in healthy subjects, it is even more essential to evaluate the ethics, logistics, patient's and doctor's acceptability, acute and late toxic effect, patient accrual and compliance of treatment. Furthermore, the decision-making process about participating in a cancer chemoprevention trial is often poorly understood. Adherence to a cancer prevention trial requires in fact a strong sense of awareness and an ability to carefully assess risks and benefits. We review the main aspects in the chemo-preventive approach to patients at high risk for breast and ovarian cancer, focusing on different pharmacological risk reduction strategies, ongoing phase III chemoprevention studies in carriers of BRCA1/2 germline mutation, the psychological and clinical factors implicated in decision making about a trial, and the possible impact of the trial design on the overall acceptability and adherence.

Opportunities and challenges of next-generation DNA sequencing for breast units

BACKGROUND

The aim of this review is to introduce the topic of next-generation DNA sequencing, a new technology that is being introduced into clinical practice, and to explain the potential impact for breast cancer surgeons and the wider breast cancer multidisciplinary team.

METHODS

The PubMed database was used to identify relevant studies relating to breast cancer genetics. This evidence was then used to provide context and background information to demonstrate how next-generation sequencing (NGS) might change breast cancer practice.

RESULTS

With NGS, breast cancer clinicians will know whether their patients carry high-risk mutations in genes, such as BRCA1 or BRCA2, before the start of treatment. This could alter treatment decisions; for instance, more women might opt for mastectomy instead of breast-conserving surgery, or for bilateral rather than unilateral surgery.

CONCLUSION

The introduction of NGS will have a significant impact on breast cancer services in the near future. Speed of testing will improve in regions of the world where NGS is adopted in place of conventional sequencing, and, as costs decrease, genetic testing will also become accessible and realistic in less well funded health economies. This will create opportunities to improve patient treatment and challenges for the breast cancer multidisciplinary team.

Risk management options elected by women after testing positive for a BRCA mutation

OBJECTIVE

To assess the uptake of risk-reducing options for the management of ovarian and breast cancer risk in BRCA mutation carriers in a large community based integrated health system in Northern California.

METHODS

A retrospective cohort of deleterious BRCA mutation carriers (1995-2012) was evaluated for consistency with NCCN guidelines for risk reducing salpingo-oophorectomy (RRSO) by age of 35-40, risk reducing mastectomy (RRM), as well as surveillance practices, including pelvic ultrasound, CA 125, mammogram, and breast MRI. Secondary outcomes included the use of chemoprevention and hormone replacement.

RESULTS

Of the 305 eligible women, 170 were BRCA1 positive, and 135 were BRCA2 positive. Seventy four percent underwent RRSO with only 17% under age 40, while 44% underwent RRM. The median time from the test to both RRSO and RRM was 6 months. In the first year after BRCA diagnosis, 45% underwent a pelvic ultrasound, dropping to 2.3% by year 5. In year 1, 47% had a CA 125, dropping to 2% by year 5. The number of women undergoing annual MRI and mammogram fell similarly over time. Sixteen percent of BRCA carriers used oral contraceptives (OCPs) and only one patient used tamoxifen for chemoprevention.

CONCLUSION

Uptake of RRSO in BRCA carriers in a population based health system is high, however the majority of women do not have RRSO by the NCCN recommended age. Compliance with surveillance is low and rapidly declines even 1 year out from testing. Attention needs to be focused on the earlier identification of BRCA mutation carriers with consolidated and standardized care to improve risk reduction.

Oral contraceptives and risk of ovarian cancer and breast cancer among high-risk women: a systematic review and meta-analysis

PURPOSE

To estimate the risks of ovarian cancer and breast cancer associated with oral contraceptive (OC) use among women at elevated risk owing to mutations in BRCA1/2 or a strong family history.

METHODS

We searched PubMed, Embase, the Cochrane Database of Systematic Reviews, and ClinicalTrials.gov for studies published 2000 to 2012 that evaluated associations between OC use and breast or ovarian cancer among women who are carriers of a BRCA1/2 mutation or have a family history of breast or ovarian cancer.

RESULTS

From 6,476 unique citations, we identified six studies examining ovarian cancer risk in BRCA1/2 mutation carriers and eight studies examining breast cancer risk in BRCA1/2 mutation carriers. For BRCA1/2 mutation carriers combined, meta-analysis showed an inverse association between OC use and ovarian cancer (odds ratio [OR], 0.58; 95% CI, 0.46 to 0.73) and a nonstatistically significant association with breast cancer (OR, 1.21; 95% CI, 0.93 to 1.58). Findings were similar when examining BRCA1 and BRCA2 mutation carriers separately. Data were inadequate to perform meta-analyses examining duration or timing of use. For women with a family history of ovarian or breast cancer, we identified four studies examining risk for ovarian cancer and three for breast cancer, but differences between studies precluded combining the data for meta-analyses, and no overall pattern could be discerned.

CONCLUSION

Our analyses suggest that associations between ever use of OCs and ovarian and breast cancer among women who are BRCA1 or BRCA2 mutation carriers are similar to those reported for the general population.

Oral contraceptive use and risk of breast, cervical, colorectal, and endometrial cancers: a systematic review

Oral contraceptives may influence the risk of certain cancers. As part of the AHRQ Evidence Report, Oral Contraceptive Use for the Primary Prevention of Ovarian Cancer, we conducted a systematic review to estimate associations between oral contraceptive use and breast, cervical, colorectal, and endometrial cancer incidence. We searched PubMed, Embase, and Cochrane Database of Systematic Reviews. Study inclusion criteria were women taking oral contraceptives for contraception or ovarian cancer prevention; includes comparison group with no oral contraceptive use; study reports quantitative associations between oral contraceptive exposure and relevant cancers; controlled study or pooled patient-level meta-analyses; sample size for nonrandomized studies ≥100; peer-reviewed, English-language; published from January 1, 2000 forward. Random-effects meta-analyses were conducted by estimating pooled ORs with 95% confidence intervals (CIs). We included 44 breast, 12 cervical, 11 colorectal, and 9 endometrial cancers studies. Breast cancer incidence was slightly but significantly increased in users (OR, 1.08; CI, 1.00-1.17); results show a higher risk associated with more recent use of oral contraceptives. Risk of cervical cancer was increased with duration of oral contraceptive use in women with human papillomavirus infection; heterogeneity prevented meta-analysis. Colorectal cancer (OR, 0.86; CI, 0.79-0.95) and endometrial cancer incidences (OR, 0.57; CI, 0.43-0.77) were significantly reduced by oral contraceptive use. Compared with never use, ever use of oral contraceptives is significantly associated with decreases in colorectal and endometrial cancers and increases in breast cancers. Although elevated breast cancer risk was small, relatively high incidence of breast cancers means that oral contraceptives may contribute to a substantial number of cases.

Does and should breast cancer genetic counselling include lifestyle advice?

To optimally inform counselees about their and their relatives' risks, information about lifestyle risk factors, e.g. physical activity and alcohol consumption, might be discussed in breast cancer genetic counselling. This study explored whether lifestyle was discussed, on whose initiative, whether information and/or advice was given, and whether discussion of lifestyle was related to counselees' characteristics and their causal attributions. First and follow-up consultations with 192 consecutive counselees for breast cancer genetic counselling were videotaped and coded for discussion of lifestyle topics. Counselees completed web-based questionnaires before the initial and after the final consultation. With 52 (27%) counselees lifestyle was discussed, either in the first, or the final consultation, or both. Counselees mostly raised the topic (60%). Counsellors provided information about lifestyle risk factors to 19% and lifestyle advice to 6% of the counselees. Discussion of lifestyle was not associated with counselees' characteristics or causal attributions. Post-counselling, more affected counselees considered lifestyle as a cause of their breast cancer (29%) compared to pre-counselling (15%; p = 0.003). Information and advice about lifestyle risk factors was infrequently provided, both with breast cancer unaffected and affected counselees and with those who did and did not consider their lifestyle as a cause of their breast cancer. Modifiable lifestyle factors could be discussed more frequently to optimally inform counselees about possible ways to reduce their risk. Counsellors should be educated about effects of lifestyle and research should be conducted on how to best integrate lifestyle information in breast cancer genetic counselling.

Establishing a program for individuals at high risk for breast cancer

Our need to create a program for individuals at high risk for breast cancer development led us to research the available data on such programs. In this paper, we summarize our findings and our thinking process as we developed our own program. Breast cancer incidence is increasing worldwide. Even though there are known risk factors for breast cancer development, approximately 60% of patients with breast cancer have no known risk factor, although this situation will probably change with further research, especially in genetics. For patients with risk factors based on personal or family history, different models are available for assessing and quantifying risk. Assignment of risk levels permits tailored screening and risk reduction strategies. Potential benefits of specialized programs for women with high breast cancer risk include more cost -effective interventions as a result of patient stratification on the basis of risk; generation of valuable data to advance science; and differentiation of breast programs from other breast cancer units, which can result in increased revenue that can be directed to further improvements in patient care. Guidelines for care of patients at high risk for breast cancer are available from various groups. However, running a high-risk breast program involves much more than applying a guideline. Each high-risk program needs to be designed by its institution with consideration of local resources and country legislation, especially related to genetic issues. Development of a successful high-risk program includes identifying strengths, weaknesses, opportunities, and threats; developing a promotion plan; choosing a risk assessment tool; defining "high risk"; and planning screening and risk reduction strategies for the specific population served by the program. The information in this article may be useful for other institutions considering creation of programs for patients with high breast cancer risk.

Endometrial and ovarian cancer in lynch syndrome

Lynch syndrome (LS) is an autosomal dominant familial cancer risk syndrome that occurs due to a germline mutation in one of several mismatch repair genes and is associated with an increased risk of colorectal, endometrial, and ovarian cancer. The risk of endometrial cancer equals or exceeds that of colorectal cancer in women with LS. The diagnosis of gynecologic cancer precedes that of colorectal cancer in over half of women with metachronous gynecologic and colon cancers, making gynecologic cancer a "sentinel cancer" for LS. There are no studies addressing the effectiveness or safety of chemoprevention for women with LS. Surveillance with gynecologic examination including assessment of symptoms, transvaginal pelvic ultrasonography, endometrial biopsy, and CA125 tumor marker assessment can be offered, but has not been shown to improve outcomes for these patients. Prophylactic hysterectomy with bilateral salpingo-oophorectomy performed after the completion of childbearing may be offered for gynecologic cancer prevention.

Identifying opportunities for cancer prevention during preadolescence and adolescence: puberty as a window of susceptibility

PURPOSE

Early life exposures during times of rapid growth and development are recognized increasingly to impact later life. Epidemiologic studies document an association between exposures at critical windows of susceptibility with outcomes as diverse as childhood and adult obesity, timing of menarche, and risk for hypertension or breast cancer.

METHODS

This article briefly reviews the concept of windows of susceptibility for providers who care for adolescent patients.

RESULTS

The theoretical bases for windows of susceptibility is examined, evaluating the relationship between pubertal change and breast cancer as a paradigm, and reviewing the underlying mechanisms, such as epigenetic modification.

CONCLUSIONS

The long-term sequela of responses to early exposures may impact other adult morbidities; addressing these exposures represents an important challenge for contemporary medicine.