Menopausal hormone therapy and risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition

Reappraising 21 years of the WHI study: Putting the findings in context for clinical practice

Menopausal hormone treatment (MHT) is recommended for the management of menopause symptoms. The Women's Health Initiative (WHI) placebo-controlled randomised study examined the effects of continuous combined or estrogen-only MHT on the risk of non-communicable diseases (NCDs) in post-menopausal women. The study was terminated prematurely after an interim analysis showed an increased risk of breast cancer diagnosis, which led to a rapid decrease in MHT use worldwide. Subsequently, limitations of the study design and its interpretation in the context of other clinical studies has contributed to a more nuanced appreciation of the risk-benefit profile of differing MHT regimens regarding risk associated with the class of progestogen prescribed, its pattern of prescription, duration of use and timing of initiation related to menopause onset. This review provides a contextual interpretation of the WHI placebo-controlled study and evaluates the impact of bioidentical MHT, with a focus on combined therapies containing micronised progesterone, on the risk of chronic NCDs in post-menopausal women.

Impact of menopausal hormone therapy on colorectal cancer risk-A systematic review

Colorectal cancer (CRC) is the second most frequently diagnosed cancer in females worldwide. Menopausal hormone therapy (MHT) has been proposed as a potential protective factor for the development of CRC. Yet, the available evidence is controversial. Thus, we aimed at summarizing the current evidence on the effect of MHT on CRC through a systematic review. A systematic literature search identified 1001 potentially relevant articles, out of which 57 original studies and nine meta-analyses were deemed eligible for the final synthesis. The evidence synthesis showed the following: (1) MHT showed a heterogeneity in findings for CRC risk with a slight tendency to a neutral or protective effect; (2) MHT effect was either neutral or protective on colorectal adenoma; (3) MHT had no impact on tumour grade, subsite and histologic types; (4) MHT was not associated with CRC mortality; and (5) MHT showed heterogeneous effects on CRC stage and invasiveness, respectively. In summary, despite some evidence pointing towards a protective effect of MHT on CRC, MHT is currently not recommended for primary CRC prevention by international guidelines due to several important, potentially harmful effects.

Cetuximab versus bevacizumab maintenance following prior 8-cycle modified FOLFOXIRI plus cetuximab in Asian postmenopausal women with treatment-naive KRAS and BRAF wild-type metastatic colorectal cancer

OBJECTIVE

To assess the efficacy and safety of cetuximab (CE) versus bevacizumab (BE) maintenance treatment after prior 8-cycle modified 5-fluorouracil, folinate, oxaliplatin, and irinotecan (FOLFOXIRI) plus CE induction therapy in treatment-naive KRAS and BRAF wild-type (wt) metastatic colorectal cancer (mCRC).

METHODS

From 2012 to 2017, prospectively maintained databases were reviewed to assess Asian postmenopausal women with treatment-naive KRAS and BRAF wt mCRC who underwent modified FOLFOXIRI plus CE induction therapy, followed by CE or BE maintenance until disease progression or death. Co-primary clinical endpoints were progression-free survival (PFS) and overall survival (OS).

RESULTS

A total of 222 women were included (CE n = 110 and BE n = 112). At a median follow-up of 27.0 months (interquartile range, 6.5-38.6 months), median PFS was 21.9 months (95% confidence interval [CI] 16.4-24.4) and 17.7 months (95% CI 11.3-19.0) for CE and BE groups, respectively (hazard ratio [HR] 0.31, 95% CI 0.15-0.46); median OS was 26.0 months (95% CI 23.4-28.7) and 22.7 months (95% CI 21.2-24.3) for CE and BE groups, respectively (HR 0.22, 95% CI 0.11-0.37).

CONCLUSIONS

CE maintenance treatment is more poorly tolerated but has a slightly more modest survival benefit compared with BE maintenance treatment in mCRC.

Cetuximab versus bevacizumab following prior FOLFOXIRI and bevacizumab in postmenopausal women with advanced KRAS and BRAF wild-type colorectal cancer: a retrospective study

BACKGROUND

An upgraded understanding of factors (sex/estrogen) associated with survival benefit in advanced colorectal carcinoma (CRC) could improve personalised management and provide innovative insights into anti-tumour mechanisms. The aim of this study was to assess the efficacy and safety of cetuximab (CET) versus bevacizumab (BEV) following prior 12 cycles of fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI) plus BEV in postmenopausal women with advanced KRAS and BRAF wild-type (wt) CRC.

METHODS

Prospectively maintained databases were reviewed from 2013 to 2017 to assess postmenopausal women with advanced KRAS and BRAF wt CRC who received up to 12 cycles of FOLFOXIRI plus BEV inductive treatment, followed by CET or BEV maintenance treatment. The primary endpoints were overall survival (OS), progression-free survival (PFS), response rate. The secondary endpoint was the rate of adverse events (AEs).

RESULTS

At a median follow-up of 27.0 months (IQR 25.1-29.2), significant difference was detected in median OS (17.7 months [95% confidence interval [CI], 16.2-18.6] for CET vs. 11.7 months [95% CI, 10.4-12.8] for BEV; hazard ratio [HR], 0.63; 95% CI, 0.44-0.89; p=0.007); Median PFS was 10.7 months (95% CI, 9.8-11.3) for CET vs. 8.4 months (95% CI, 7.2-9.6) for BEV (HR, 0.67; 95% CI 0.47-0.94; p=0.02). Dose reduction due to intolerable AEs occurred in 29 cases (24 [24.0%] for CET vs. 5 [4.8%] for BEV; p< 0.001).

CONCLUSIONS

CET tends to be superior survival benefit when compared with BEV, with tolerated AEs.

Menopausal hormone therapy and colorectal cancer: a linkage between nationwide registries in Norway

OBJECTIVES

With the present study, we aimed to investigate the association between menopausal hormone therapy (HT) and risk of colorectal cancer (CRC).

SETTING

Cohort study based on the linkage of Norwegian population-based registries.

PARTICIPANTS

We selected 466822 Norwegian women, aged 55-79, alive and residing in Norway as of 1 January 2004, and we followed them from 2004 to 2008. Each woman contributed person-years at risk as non-user, current user and/or past HT user.

OUTCOME MEASURES

The outcome of interest was adenocarcinoma of the colorectal tract, overall, by anatomic site and stage at diagnosis. Incidence rate ratios (RRs) with 95% CIs were estimated by Poisson regression and were used to evaluate the association between HT and CRC incidence.

RESULTS

During the median follow-up of 4.8 years, 138 655 (30%) women received HT and 3799 (0.8%) incident CRCs occurred. Current, but not past, use of HT was associated with a lower risk of CRC (RR 0.88; 95% CI 0.80 to 0.98). RRs for localised, regionally advanced and metastatic CRC were 1.13 (95% CI 0.91 to 1.41), 0.81 (95% CI 0.70 to 0.94) and 0.79 (95% CI 0.62 to 1.00), respectively. RRs for current use of oestrogen therapy (ET) were 0.91 (95% CI 0.80 to 1.04) while RR for current use of combined oestrogen-progestin therapy (EPT) was 0.85 (95% CI 0.70 to 1.03), as compared with no use of HT. The same figures for ET and EPT in oral formulations were 0.83 (95% CI 0.68 to 1.03) and 0.86 (95% CI 0.71 to 1.05), respectively.

CONCLUSIONS

In our nationwide cohort study, HT use lowered the risk of CRC, specifically the most advanced CRC.

Current Evidence on Associations of Nutritional Factors with Ovarian Reserve and Timing of Menopause: A Systematic Review

Ovarian aging is thought to be influenced by environmental factors, including nutrition. The aim of this study was to systematically review current evidence on the associations between nutritional factors, ovarian reserve, and age at menopause. PubMed and Scopus were structurally searched until May 2016. Original studies, with either observational or interventional designs, that examined the associations of nutritional factors (serum or dietary nutrients, food groups, and/or dietary patterns) with different ovarian reserve markers and/or timing of menopause were considered eligible. Twenty-six studies met the inclusion criteria: 17 studies on ovarian reserve markers and 9 studies on menopausal age. Significant diversity was observed in nutritional factors examined across studies. In the study of nutritional factors, associations of serum 25-hydroxyvitamin D [25(OH)D] concentration and intakes of soy or soy products with ovarian reserve have been the most investigated. For associations with menopausal age, intakes of total fat, fiber, and soy products have been mainly examined. Significant associations with ovarian reserve markers were found in 4 of 7 studies on serum 25(OH)D, 2 of 6 studies on soy or soy products, 1 of 2 studies on fiber intake, 1 study on serum zinc and copper concentrations, and 1 study on serum antioxidant concentrations. Studies on nutritional factors and menopausal age provided inconsistent findings, some of which suggested modest associations. Although there is some promising evidence on the influential role of nutrition in ovarian aging, a limited number of studies, heterogeneous in their design and study of nutritional factors, makes it difficult to draw definite conclusions. To better understand this issue, examination of associations of dietary intakes or dietary patterns with more precise markers of ovarian reserve, such as anti-mullerian hormone and antral follicle count, with age at menopause is needed. In addition, to explore whether nutritional factors alter the process of ovarian aging, an examination of changes in ovarian reserve markers should be considered.

Gene signatures of estrogen and progesterone receptor pathways predict the prognosis of colorectal cancer

The associations of estrogen receptor (ER) and progesterone receptor (PR) pathways with the prognosis of colorectal cancer (CRC) are still controversial. The aim of this study was to readdress these issues by introducing a gene signature-based approach to semiquantitate pathway activity. In this approach, the ER and PR pathway activities in CRC were computed based on the expression profiles of the signature genes of ER and PR pathways, respectively. The results showed that the ER pathway activity was progressively significantly decreased from normal colorectal mucosa, colorectal adenoma to CRC. ER pathway signaling was a favorable factor for the presence of microsatellite stability (MSS) in CRC in seven cohorts tested, while was an unfavorable factor for cancer recurrence in all four CRC cohorts tested (n = 1122; overall HR: 0.311, 95% CI: 0.199-0.488, P < 0.001). Subset stratification in stage II patients showed that ER pathway remained significantly inversely associated with recurrence. PR pathway was also suppressed in colorectal tumors and inversely associated with recurrence of CRC, but to a much lesser extent than ER pathway. Moreover, the inverse association of PR pathway with cancer recurrence was more likely observed in CRC with high ER pathway activity, suggesting the interactions between the two pathways. PR pathway was not associated with MSS in CRC, but it was more significant than ER pathway associated with advance cancer stages and cancer response to adjuvant chemotherapy. These results suggested the potential application of the gene signatures of ER and PR pathways, especially the former, as novel markers for prognosis and management of CRC.

The influence of hormone therapies on colon and rectal cancer

Exogenous sex hormones seem to play a role in colorectal carcinogenesis. Little is known about the influence of different types or durations of postmenopausal hormone therapy (HT) on colorectal cancer risk. A nationwide cohort of women 50-79 years old without previous cancer (n = 1,006,219) were followed 1995-2009. Information on HT exposures was from the National Prescription Register and updated daily, while information on colon (n = 8377) and rectal cancers (n = 4742) were from the National Cancer Registry. Potential confounders were obtained from other national registers. Poisson regression analyses with 5-year age bands included hormone exposures as time-dependent covariates. Use of estrogen-only therapy and combined therapy were associated with decreased risks of colon cancer (adjusted incidence rate ratio 0.77, 95 % confidence interval 0.68-0.86 and 0.88, 0.80-0.96) and rectal cancer (0.83, 0.72-0.96 and 0.89, 0.80-1.00), compared to never users. Transdermal estrogen-only therapy implied more protection than oral administration, while no significant influence was found of regimen, progestin type, nor of tibolone. The benefit of HT was stronger for long-term hormone users; and hormone users were at lower risk of advanced stage of colorectal cancer, which seems supportive for a causal association between hormone therapy and colorectal cancer.

Cohort Profile: The French E3N Cohort Study

The E3N (Etude Epidémiologique auprès de femmes de la Mutuelle Générale de l'Education Nationale) cohort was initiated in 1990 to investigate therisk factors associated with cancer and other major non-communicable diseases in women. The participants were insured through a national health system that primarily covered teachers, and were enrolled from 1990 after returning baseline self-administered questionnaires and providing informed consent. The cohort comprised nearly 100,000 women with baseline ages ranging from 40 to 65 years. Follow-up questionnaires were sent approximately every 2-3 years after the baseline and addressed general and lifestyle characteristics together with medical events (cancer, cardiovascular diseases, diabetes, depression, fractures and asthma, among others). The follow-up questionnaire response rate remained stable at approximately 80%. A biological material bank was generated and included blood samples collected from 25,000 women and saliva samples from an additional 47,000 women. Ageing among the E3N cohort provided the opportunity to investigate factors related to age-related diseases and conditions as well as disease survival. The new E4N complementary cohort (Epidemiology 4 kNowledge), which comprises the children and grandchildren of the E3N cohort as well as the children's fathers, will allow researchers to investigate key life periods during which exposures to environmental factors most strongly influence the later disease risk. The E3N and E4N cohort data will be used to investigate diseases and risk factors through a transgenerational approach. Requests for collaborations are welcome, particularly those in conjunction with rare diseases.

Associations of hormone replacement therapy and oral contraceptives with risk of colorectal cancer defined by clinicopathological factors, beta-catenin alterations, expression of cyclin D1, p53, and microsatellite-instability

Background

Postmenopausal hormone therapy (HRT) and oral contraceptive (OC) use have in several studies been reported to be associated with a decreased colorectal cancer (CRC) risk. However, data on the association between HRT and OC and risk of different clinicopathological and molecular subsets of CRC are lacking. The aim of this molecular pathological epidemiology study was therefore to evaluate the associations between HRT and OC use and risk of specific CRC subgroups, overall and by tumour site.

Method

In the population-based prospective cohort study Mamö Diet and Cancer, including 17035 women, 304 cases of CRC were diagnosed up until 31 December 2008. Immunohistochemical expression of beta-catenin, cyclin D1, p53 and MSI-screening status had previously been assessed in tissue microarrays with tumours from 280 cases. HRT was assessed as current use of combined HRT (CHRT) or unopposed oestrogen (ERT), and analysed among 12583 peri-and postmenopausal women. OC use was assessed as ever vs never use among all women in the cohort. A multivariate Cox regression model was applied to determine hazard ratios for risk of CRC, overall and according to molecular subgroups, in relation to HRT and OC use.

Results

There was no significantly reduced risk of CRC by CHRT or ERT use, however a reduced risk of T-stage 1–2 tumours was seen among CHRT users (HR: 0.24; 95% CI: 0.09-0.77).

Analysis stratified by tumour location revealed a reduced overall risk of rectal, but not colon, cancer among CHRT and ERT users, including T stage 1–2, lymph node negative, distant metastasis-free, cyclin D1 - and p53 negative tumours.

In unadjusted analysis, OC use was significantly associated with a reduced overall risk of CRC (HR: 0.56; 95% CI: 0.44-0.71), but this significance was not retained in adjusted analysis (HR: 1.05: 95% CI: 0.80-1.37). A similar risk reduction was seen for the majority of clinicopathological and molecular subgroups.

Conclusion

Our findings provide information on the relationship between use of HRT and OC and risk of clinicopathological and molecular subsets of CRC.

Molecular pathways: Estrogen pathway in colorectal cancer

Worldwide, colorectal cancer has a higher incidence rate in men than in women, suggesting a protective role for sex hormones in the development of the disease. Preclinical data support a role for estrogen and its receptors in the initiation and progression of colorectal cancer and establishes that protective effects of estrogen are exerted through ERβ. Hormone replacement therapy (HRT) in postmenopausal women as well as consumption of soy reduces the incidence of colorectal cancer. In the Women's Health Initiative trial, use of HRT in postmenopausal women reduced the risk of colon cancer by 56% [95% confidence interval (CI), 0.38-0.81; P = 0.003]. A recent meta-analysis showed that in women, consumption of soy reduced the risk of colon cancer by 21% (95% CI, 0.03-0.35; P = 0.026). In this review, using the preclinical data, we translate the findings in the clinical trials and observational studies to define the role of estrogen in the prevention of colorectal cancer. We hypothesize that sometime during the tumorigenesis process ERβ expression in colonocytes is lost and the estrogen ligand, HRT, or soy products, exerts its effects through preventing this loss. Thus, in the adenoma-to-carcinoma continuum, timing of HRT is a significant determinant of the observed benefit from this intervention. We further argue that the protective effects of estrogen are limited to certain molecular subtypes. Successful development of estrogen modulators for prevention of colorectal cancer depends on identification of susceptible colorectal cancer population(s). Thus, research to better understand the estrogen pathway is fundamental for clinical delivery of these agents.

Estrogen plus progestin and colorectal cancer incidence and mortality

PURPOSE

During the intervention phase in the Women's Health Initiative (WHI) clinical trial, use of estrogen plus progestin reduced the colorectal cancer diagnosis rate, but the cancers were found at a substantially higher stage. To assess the clinical relevance of the findings, analyses of the influence of combined hormone therapy on colorectal cancer incidence and colorectal cancer mortality were conducted after extended follow-up.

PATIENTS AND METHODS

The WHI study was a randomized, double-blind, placebo-controlled clinical trial involving 16,608 postmenopausal women with an intact uterus who were randomly assigned to daily 0.625 mg conjugated equine estrogen plus 2.5 mg medroxyprogesterone acetate (n = 8,506) or matching placebo (n = 8,102). Colorectal cancer diagnosis rates and colorectal cancer mortality were assessed.

RESULTS

After a mean of 5.6 years (standard deviation [SD], 1.03 years) of intervention and 11.6 years (SD, 3.1 years) of total follow-up, fewer colorectal cancers were diagnosed in the combined hormone therapy group compared with the placebo group (diagnoses/year, 0.12% v 0.16%; hazard ratio [HR], 0.72; 95% CI, 0.56 to 0.94; P = .014). Bowel screening examinations were comparable between groups throughout. Cancers in the combined hormone therapy group more commonly had positive lymph nodes (50.5% v 28.6%; P < .001) and were at higher stage (regional or distant, 68.8% v 51.4%; P = .003). Although not statistically significant, there was a higher number of colorectal cancer deaths in the combined hormone therapy group (37 v 27 deaths; 0.04% v 0.03%; HR, 1.29; 95% CI, 0.78 to 2.11; P = .320).

CONCLUSION

The findings, suggestive of diagnostic delay, do not support a clinically meaningful benefit for combined hormone therapy on colorectal cancer.

The treatment of climacteric symptoms

BACKGROUND

Peri- and postmenopausal women commonly suffer from climacteric symptoms. In this article, we provide information to help physicians recognize climacteric symptoms and treat them appropriately.

METHODS

The information presented here is based on a selective search of the literature for pertinent articles that appeared from 2008 to early 2011, including the German S3 guideline on hormone therapy (HT) during and after menopause, which was published in 2009.

RESULTS

Perimenopausal women often suffer from climacteric symptoms. Typically, women undergoing menopause complain of heat waves and vaginal dryness. According to randomized controlled trials as well as national and international guidelines, HT is the most effective treatment for vasomotor symptoms and also improves vulvovaginal atrophy; for the latter indication, HT is preferably administered locally. Vaginal estrogen therapy lowers the frequency of recurrent urinary tract infections. However, HT is associated with an increased risk for a number of diseases, including stroke, thromboembolic events, gall-bladder diseases, and breast cancer. Alternative treatments for climacteric symptoms have little or no efficacy.

CONCLUSION

HT should only be used to treat climacteric symptoms after extensive patient education about its benefits and risks. Participatory decision-making is desirable. The generalized use of HT by all women with climacteric symptoms cannot be recommended.

Menopausal hormone therapy and risk of gastrointestinal cancer: nested case-control study within a prospective cohort, and meta-analysis

Use of menopausal hormone therapy (HT) has been associated with reduced risk of colorectal cancer; evidence for its effect on other gastrointestinal cancers is limited. We conducted a nested case-control study within a UK cohort, and meta-analyses combining our results with those from published studies. Our study included women aged 50+ in the UK General Practice Research Database (GPRD): 1,054 with oesophageal, 750 with gastric and 4,708 with colorectal cancer, and 5 age- and practice-matched controls per case. Relative risks (RRs) and 95% confidence intervals (CIs) for cancer in relation to prospectively-recorded HT prescriptions were estimated by conditional logistic regression. Women prescribed HT had a reduced risk of oesophageal cancer (adjusted RR for 1+ vs. no HT prescriptions, 0.68, 95% CI 0.53-0.88; p = 0.004), gastric cancer (0.75, 0.54-1.05; p = 0.1) and colorectal cancer (0.81, 0.73-0.90; p < 0.001). There were no significant differences in cancer risk by HT type, estimated duration of HT use or between past and current users. In meta-analyses, risks for ever vs. never use of HT were significantly reduced for all three cancers (summary RR for oesophageal cancer, 0.68, 0.55-0.84, p < 0.001; for gastric cancer, 0.78, 0.65-0.94, p = 0.008; for colorectal cancer, 0.84, 0.81-0.88, p < 0.001). In high-income countries, estimated incidence over 5 years of these three cancers combined in women aged 50-64 was 2.9/1,000 in HT users and 3.6/1,000 in never users. The absolute reduction in risk of these cancers in HT users is small compared to the HT-associated increased risk of breast cancer.

Chemoprevention of colorectal cancer: a role for ursodeoxycholic acid, folate and hormone replacement treatment?

Chemoprevention of colorectal cancer has been an intense focus of research for many years. Among the possible candidate agents, ursodeoxycholic acid, folate, and hormone replacement therapy have been recently investigated with conflicting data. Experimental evidence shows that UDCA, folate and HRT target critical molecular events important for colon carcinogenesis. In animal models of sporadic, familial and inflammatory-associated cancers, they have shown to reduce colonic neoplasms. Observational studies have shown compelling evidence of possible protective effects of all three agents. However, randomised-controlled studies have yielded disappointing results, raising the issues of possible harm rather than protective effect for some of them. In this review experimental and clinical data on UDCA, folate and HRT as potential chemopreventive agents are discussed.

Oral contraceptives, reproductive history and risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition

BACKGROUND

Oral contraceptive use and reproductive factors may initiate long-term changes to the hormonal milieu and thereby, possibly influence colorectal cancer risk.

METHODS

We examined the association of hormonal and reproductive factors with risk of colorectal cancer among 337,802 women in the European Prospective Investigation into Cancer and Nutrition, of whom 1878 developed colorectal cancer.

RESULTS

After stratification for center and age, and adjustment for body mass index, smoking, diabetes mellitus, physical activity and alcohol consumption, ever use of oral contraceptives was marginally inversely associated with colorectal cancer risk (hazard ratio (HR), 0.92; 95% confidence interval (CI), 0.83-1.02), although this association was stronger among post-menopausal women (HR, 0.84; 95% CI: 0.74-0.95). Duration of oral contraceptive use and reproductive factors, including age at menarche, age at menopause, type of menopause, ever having an abortion, parity, age at first full-term pregnancy and breastfeeding, were not associated with colorectal cancer risk.

CONCLUSION

Our findings provide limited support for a potential inverse association between oral contraceptives and colorectal cancer risk.