Population-based analysis of colorectal cancer risk after oophorectomy

Sex differences in colorectal cancer: with a focus on sex hormone-gut microbiome axis

Sexual dimorphism has been observed in the incidence and prognosis of colorectal cancer (CRC), with men generally exhibiting a slightly higher incidence than women. Research suggests that this difference may be attributed to variations in sex steroid hormone levels and the gut microbiome. The gut microbiome in CRC shows variations in composition and function between the sexes, leading to the concept of 'microgenderome' and 'sex hormone-gut microbiome axis.' Conventional research indicates that estrogens, by promoting a more favorable gut microbiota, may reduce the risk of CRC. Conversely, androgens may have a direct pro-tumorigenic effect by increasing the proportion of opportunistic pathogens. The gut microbiota may also influence sex hormone levels by expressing specific enzymes or directly affecting gonadal function. However, this area remains controversial. This review aims to explore the differences in sex hormone in CRC incidence, the phenomenon of sexual dimorphism within the gut microbiome, and the intricate interplay of the sex hormone-gut microbiome axis in CRC. The objective is to gain a better understanding of these interactions and their potential clinical implications, as well as to introduce innovative approaches to CRC treatment.

Bilateral Oophorectomy and Colorectal Cancer Incidence and Mortality in the Women's Health Initiative

BACKGROUND

The few cohort studies examining oophorectomy and colorectal cancer risk provide mixed results. Therefore, we examined this issue in Women's Health Initiative Observational Study participants.

METHODS

A total of 71,312 postmenopausal women were followed for 22.1 years (median). At enrollment, 55,643 (78%) had intact ovaries and 15,669 (22%) had undergone a bilateral oophorectomy. Colorectal cancers were verified by central medical record review with mortality findings enhanced by National Death Index queries.

RESULTS

With 1,421 incident colorectal cancers, 450 colorectal cancer-specific mortalities, after controlling for covariates, bilateral oophorectomy was not associated with colorectal cancer incidence or colorectal cancer mortality.

CONCLUSIONS

No significant associations between oophorectomy and colorectal cancer incidence and mortality were seen in a large cohort study with long follow-up.

IMPACT

As the oophorectomy and colorectal cancer question remains open, further studies of high quality, even with null findings, should be encouraged.

The increased risk of colorectal cancer in the women who underwent hysterectomy from the South Korean National Health Insurance Database

BACKGROUND

Several population-based studies and observational studies have shown that oophorectomy is associated with an increased risk of colorectal cancer (CRC), and hormone replacement therapy has been associated with a reduction in the risk of colorectal cancer. This study was carried out to investigate whether hysterectomy, which may affect the levels of female hormones, is associated with a risk of cancer of the specific gastrointestinal tract.

METHODS

This population-based retrospective cohort study was conducted using insurance data provided by the Health Insurance Review and Assessment Service (HIRA) from January 1, 2007, to December 31, 2020. The hysterectomy group included 40- to 59-year-old women who underwent hysterectomy with uterine leiomyoma or uterine endometriosis from January 1, 2011, to December 31, 2014. The control group included women aged 40 to 59 years who visited medical institutions for medical examination from January 1, 2011 to December 31, 2014.

RESULTS

The hysterectomy and non-hysterectomhy groups comprised 66,204 and 89,768 subjects, respectively. The median ages in the non-hysterectomy group and hysterectomy group were 48 (range: 43-53) and 46 (range: 44-49) years, respectively. In the unadjusted results of the analysis, all colorectal cancer (CRC) increased in the hysterectomy alone group (HR 1.222, 95% confidence interval (CI) 1.016-1.47, p = 0.033), sigmoid colon cancer increased in the hysterectomy alone group (HR 1.71, 95% CI 1.073-2.724, p = 0.024), and rectal cancer increased in the hysterectomy with adnexal surgery group (HR 1.924, 95% CI 1.073-2.724, p = 0.002). The adjusted results showed that all CRC increased in the hysterectomy alone group (HR 1.406, 95% CI 1.057-1.871, p = 0.019), colon cancer increased in the hysterectomy alone group (HR 1.523, 95% CI 1.068-2.17, p = 0.02), and rectal cancer increased in the hysterectomy with adnexal surgery group (HR 1.933, 95% CI 1.131-3.302, p = 0.016). The all-cause mortality of GI cancer increased in the hysterectomy alone group (HR 3.495, 95% CI 1.347-9.07, p = 0.001).

CONCLUSIONS

This study showed that the risk of all CRC increased in women who underwent hysterectomy compared with women who did not. In particular, the risk of rectal cancer was significantly higher in the women who underwent hysterectomy with adnexal surgery than in the controls. There was no association between hysterectomy and other GI cancers.

Incidence of other cancer diagnoses in women with breast cancer: a retrospective cohort study with 42,248 women

PURPOSE

The aim of the present study was to determine whether women diagnosed with breast cancer (BC) have an increased incidence of other cancers, e.g., gastric cancer, lung cancer, skin cancer, and so on, compared to healthy women without a breast cancer diagnosis.

METHODS

This retrospective cohort study was based on data from the Disease Analyzer database (IQVIA) and included adult women with an initial diagnosis of BC documented in one of 1,274 general practices in Germany between January 2000 and December 2018. Women with BC were matched to women without cancer by age, index year, yearly consultation frequency, and co-diagnoses. Univariate Cox regression models were used to study the association between BC and the incidence of other cancer diagnoses.

RESULTS

21,124 women with BC and 21,124 women (mean age: 63 years) without cancer were included. Within 10 years of the index date, 14.3% of women with BC and 10.0% of women without cancer were diagnosed with cancer (p < 0.001). BC was significantly associated with the incidence of other cancer diagnoses (HR: 1.42, p < 0.001). The strongest association was observed for respiratory organ cancer (HR = 1.69, p < 0.001), followed by female genital organ cancer (HR = 1.61, p < 0.001) and cancer of lymphoid and hematopoietic tissue (HR: 1.59, p < 0.001).

CONCLUSION

The results of this study show that women with BC have an increased incidence of another cancer compared to women without cancer. Therefore, it is important to pay particular attention to the development of other malignancies during follow-up in patients with BC. This should be considered especially in patients with a proven genetic mutation.

Risk of de novo cancer after premenopausal bilateral oophorectomy

BACKGROUND

Hysterectomy is one of the most frequent gynecologic surgeries in the United States. Women undergoing hysterectomy are commonly offered bilateral oophorectomy for ovarian and breast cancer prevention. Although bilateral oophorectomy may dramatically reduce the risk of gynecologic cancers, some studies suggested that bilateral oophorectomy may be associated with an increased risk of other types of cancer, such as lung cancer and colorectal cancer. However, the results are conflicting.

OBJECTIVE

To study the association between bilateral oophorectomy and the risk of subsequent cancer of any type.

STUDY DESIGN

This population-based cohort study included all premenopausal women who underwent bilateral oophorectomy for a nonmalignant indication before the age of 50, between January 1, 1988 and December 31, 2007 in Olmsted County, Minnesota, and a random sample of age-matched (±1 year) referent women who did not undergo bilateral oophorectomy. Women with cancer before oophorectomy (or index date) or within 6 months after the index date were excluded. Time-to-event analyses were performed to assess the risk of de novo cancer. Cancer diagnosis and type were confirmed using medical record review.

RESULTS

Over a median follow-up of 18 years, the risk of any cancer did not significantly differ between the 1562 women who underwent bilateral oophorectomy before natural menopause and the 1610 referent women (adjusted hazard ratio, 0.82; 95% confidence interval, 0.66-1.03). However, women who underwent bilateral oophorectomy had a decreased risk of gynecologic cancers (adjusted hazard ratio, 0.15; 95% confidence interval, 0.06-0.34) but not of nongynecologic cancers (adjusted hazard ratio, 0.99; 95% confidence interval, 0.78-1.26). In particular, the risk of breast cancer, gastrointestinal cancer, and lung cancer did not differ between these 2 cohorts. Use of estrogen therapy through the age of 50 years in women who underwent bilateral oophorectomy did not modify the results.

CONCLUSION

Women who underwent bilateral oophorectomy before menopause have a reduced risk of gynecologic cancer but not of other types of cancer including breast cancer. Women at average risk of ovarian cancer should not consider bilateral oophorectomy for the prevention of breast cancer or other nongynecologic cancers.

Adverse childhood experiences are associated with increased risk of hysterectomy and bilateral oophorectomy: A national retrospective cohort study of women in England

Objective

To examine the associations between adverse childhood experiences (ACE) and the risk of hysterectomy and bilateral oophorectomy in a national sample of women in England.

Design

Retrospective cohort study.

Setting

A stratified random sample of households across England.

Population

2648 women aged ≥55 years in 2007 from the English Longitudinal Study of Ageing (ELSA) were included in the bilateral oophorectomy analyses and 2622 in the hysterectomy analyses.

Methods

Logistic and multinomial logistic regression analyses of the associations between categories of the ACE summary score (0, 1, 2, ≥3 ACE), eight individual ACE, and hysterectomy and bilateral oophorectomy.

Results

615 women had undergone hysterectomy and 259 women bilateral oophorectomy. We found graded associations between the summary ACE score and risk of hysterectomy and bilateral oophorectomy. In the fully adjusted model, compared with women with no ACE, those with ≥3 ACE had double the odds of hysterectomy (odds ratio [OR] 2.01, 95% confidence interval [CI] 1.30–3.11) and more than double the odds of bilateral oophorectomy (OR 2.61, 95% CI 1.54–4.42). The exclusion of women with cancer history made the associations stronger, especially in women who underwent hysterectomy at age <40 years or bilateral oophorectomy at age ≤44 years. Several individual ACE were positively associated with both outcomes.

Conclusions

ACE are associated with increased risk of hysterectomy and bilateral oophorectomy. Individual‐level covariates did not explain these associations. Our findings highlight the importance of a life course approach to understanding surgical menopause and add to our knowledge of the societal and public health impact of ACE.

Tweetable abstract

Adverse childhood experiences are associated with increased risk of hysterectomy and bilateral oophorectomy in a national sample of women in England.

Adverse childhood experiences are associated with increased risk of hysterectomy and bilateral oophorectomy in a national sample of women in England.

Linked article: This article is commented on by Walter A. Rocca, pp. 1491–1492 in this issue. To view this minicommentary visit https://doi.org/10.1111/1471-0528.17105.

Bilateral oophorectomy and rate of colorectal cancer: A prospective cohort study

Worldwide, colorectal cancer is the second most common cancer and third cause of cancer death in women. Estrogen exposure has been inversely associated with colorectal cancer. Oophorectomy reduces circulating estrogen, but the effect on colorectal cancer remains uncertain. The aim of this study was to examine the association between unilateral and bilateral oophorectomy and subsequent risk of colorectal cancer, and whether this association varied by menopausal status at time of oophorectomy, use of hormone replacement therapy (HRT) at baseline, hysterectomy and baseline body mass index (BMI). The study included 25 698 female nurses (aged ≥45 years) participating in the Danish Nurse Cohort. Nurses were followed from baseline until date of colorectal cancer, death, emigration or end of follow-up at December 31, 2018, whichever came first. We examined the association between oophorectomy and colorectal cancer (all ages and stratified by menopausal status). The potential modifying effects of hysterectomy, HRT use at baseline and BMI were investigated. During 542 140 person-years of follow-up, 863 (3.4%) nurses were diagnosed with colorectal cancer. Bilateral oophorectomy was associated with a 79% increased colorectal cancer rate, adjusted rate ratio (aRR) (95% confidence interval [CI]): 1.79 (1.33-2.42). Effect estimates following unilateral oophorectomy also showed higher rate of colorectal cancer, although less pronounced and nonstatistically significant (aRR) (95% CI): 1.25 (0.86-1.82). Similar results were seen when stratifying by menopausal status. The association was not modified by baseline HRT use, hysterectomy or BMI. Oophorectomy was associated with increased rate of colorectal cancer, with highest rates among women with bilateral oophorectomy.

Predictors of CRC Stage at Diagnosis among Male and Female Adults Participating in a Prospective Cohort Study: Findings from Alberta's Tomorrow Project

Colorectal cancer (CRC) is a leading cause of morbidity and mortality in Canada. CRC screening and other factors associated with early-stage disease can improve CRC treatment efficacy and survival. This study examined factors associated with CRC stage at diagnosis among male and female adults using data from a large prospective cohort study in Alberta, Canada. Baseline data were obtained from healthy adults aged 35–69 years participating in Alberta’s Tomorrow Project. Factors associated with CRC stage at diagnosis were evaluated using Partial Proportional Odds models. Analyses were stratified to examine sex-specific associations. A total of 267 participants (128 males and 139 females) developed CRC over the study period. Among participants, 43.0% of males and 43.2% of females were diagnosed with late-stage CRC. Social support, having children, and caffeine intake were predictors of CRC stage at diagnosis among males, while family history of CRC, pregnancy, hysterectomy, menopausal hormone therapy, lifetime number of Pap tests, and household physical activity were predictive of CRC stage at diagnosis among females. These findings highlight the importance of sex differences in susceptibility to advanced CRC diagnosis and can help inform targets for cancer prevention programs to effectively reduce advanced CRC and thus improve survival.

Hysterectomy and Risk of Breast, Colorectal, Thyroid, and Kidney Cancer - an Australian Data Linkage Study

BACKGROUND

This study aimed to investigate the associations between hysterectomy for benign indications and risk of breast, colorectal, kidney, and thyroid cancer, and to explore whether these associations are modified by removal of ovaries at the time of surgery or by age at surgery.

METHODS

We conducted a retrospective cohort study of the female population of Western Australia (n = 839,332) linking data from electoral, hospital, births, deaths, and cancer records. We used Cox regression to estimate HRs and 95% confidence intervals (CI) for the associations between hysterectomy and diagnosis of breast, colorectal, kidney, and thyroid cancers.

RESULTS

Compared with no surgery, hysterectomy without oophorectomy (hysterectomy) and hysterectomy with bilateral salpingo-oophorectomy (hysterectomy-BSO) were associated with higher risk of kidney cancer (HR, 1.32; 95% CI, 1.11-1.56 and HR, 1.29; 95% CI, 0.96-1.73, respectively). Hysterectomy, but not hysterectomy-BSO, was related to higher risk of thyroid cancer (HR, 1.38; 95% CI, 1.19-1.60). In contrast, hysterectomy (HR, 0.94; 95% CI, 0.90-0.98) and hysterectomy-BSO (HR, 0.92; 95% CI, 0.85-1.00) were associated with lower risk of breast cancer. We found no association between hysterectomy status and colorectal cancer.

CONCLUSIONS

The associations between hysterectomy and cancer varied by cancer type with increased risks for thyroid and kidney cancer, decreased risk for breast cancer, and no association for colorectal cancer.

IMPACT

As breast, colorectal, and gynecologic cancers comprise a sizeable proportion of all cancers in women, our results suggest that hysterectomy is unlikely to increase overall cancer risk; however, further research to understand the higher risk of thyroid and kidney cancer is warranted.

Ovarian conservation vs removal at the time of benign hysterectomy

Over the last 2 decades, the rate of oophorectomy at the time of hysterectomy in the United States has consistently been between 40-50%. A decline in hormone use has been observed since the release of the principal results of the Women's Health Initiative. Oophorectomy appears to be associated with an increased risk of coronary heart disease, as well as deleterious effects on overall mortality, cognitive functioning, and sexual functioning. Estrogen deficiency from surgical menopause is associated with bone mineral density loss and increased fracture risk. While hormone therapy may mitigate these effects, at no age does there appear to be a survival benefit associated with oophorectomy. Reduction of ovarian cancer risk may be accomplished with salpingectomy at the time of hysterectomy.

Removal of all ovarian tissue versus conserving ovarian tissue at time of hysterectomy in premenopausal patients with benign disease: study using routine data and data linkage

OBJECTIVE

 To conduct a nationwide study of associations between removal of all ovarian tissue versus conservation of at least one ovary at the time of hysterectomy and important health outcomes (ischaemic heart disease, cancer, and all cause mortality).

STUDY DESIGN AND SETTING

 Retrospective analysis of the English Hospital Episode Statistics database linked to national registers of deprivation indices and of deaths.

PARTICIPANTS

 113 679 patients aged 35-45 who had had a hysterectomy for benign conditions between April 2004 and March 2014.

EXPOSURES

 Bilateral ovarian removal versus no removal or unilateral ovarian removal (ovarian conservation).

MAIN OUTCOME MEASURES

 Hospital admissions for ischaemic heart disease, cancer, or attempted suicide; deaths, overall and from heart disease, cancer, or suicide. Statistical adjustments were made using Cox regression and propensity score matching for potential confounders.

RESULTS

 A third of patients had bilateral ovarian removal. Patients in the ovarian conservation group were less likely to be admitted for ischaemic heart disease after hysterectomy than were those in the bilateral removal group (adjusted hazard ratio 0.85, 95% confidence interval 0.77 to 0.93; P=0.001). They were also less likely to have a cancer related post-hysterectomy admission (adjusted hazard ratio 0.83, 0.78 to 0.89; P<0.001). A significant difference in all cause mortality was also seen: 0.60% (456/76 581) of patients with ovarian conservation compared with 1.01% (376/37 098) of patients with bilateral removal. Again, this difference in favour of ovarian conservation was significant (adjusted hazard ratio 0.64, 0.55 to 0.73; P<0.001). Fewer deaths related specifically to heart disease (adjusted hazard ratio 0.50, 0.28 to 0.90; P=0.02) and to cancer (0.54, 0.45 to 0.65; P<0.001) occurred in the ovarian conservation group than in the bilateral removal group. No significant difference between groups was found relating to suicide (attempted or completed). The results after propensity score matching were essentially unchanged.

CONCLUSION

 Patients who had ovarian conservation had a significantly lower hazard of all cause mortality compared with those who had bilateral ovarian removal and also had lower death rates from ischaemic heart disease and cancer. Consistent with this observation, admissions to hospital for both ischaemic heart disease and cancer were also lower in the ovarian conservation group than in the bilateral removal group. Although removal of both ovaries protects against subsequent development of ovarian cancer, premenopausal women should be advised that this benefit comes at the cost of an increased risk of cardiovascular disease and of other (more prevalent) cancers and higher overall mortality.

Risk of colorectal cancer with hysterectomy and oophorectomy: A systematic review and meta-analysis

BACKGROUND

Colorectal cancer (CRC) is the second most commonly diagnosed cancer worldwide in females. Sex hormones may play a protective effect in CRC pathogenesis. Ovarian sex steroid levels are reduced in premenopausal women after hysterectomy. Prospective studies have revealed an 80% decrease in serum oestradiol levels after bilateral oophorectomy in premenopausal women. We aimed to elucidate the relationship between hysterectomy or oophorectomy and risk of CRC.

METHODS

We estimated relative risk (RR) and 95% confidence intervals (95% CIs) with the meta-analysis. Cochran's Q test and Higgins I² statistic were used to check for heterogeneity. Subgroup and sensitivity analyses were performed as were Egger's and Begg's tests and the "trim-and-fill" method for publication bias analysis.

RESULTS

Risk of CRC was increased 30% for women undergoing oophorectomy relative to the general population and 24% with hysterectomy relative to no surgery. The risk was increased 22% with hysterectomy with bilateral salpingoo-ophorectomy as compared with simple hysterectomy. On subgroup analysis, risk of rectal cancer was increased 28% and colon cancer 19% with hysterectomy. Europeans seem to be sensitive to the risk of CRC, with 27% increased risk after hysterectomy. The risk of CRC after oophorectomy gradually increased with age at oophorectomy. The risk was greater with bilateral oophorectomy, with 36% increased risk, than unilateral oophorectomy, with 20% increased risk. Risk was increased 66% with time since oophorectomy 1-4 years as compared with 5-9 and ≥ 10 years.

CONCLUSIONS

Risk of CRC was increased for women undergoing hysterectomy or oophorectomy. Women with susceptibility genes for ovarian cancer or metrocarcinoma should choose oophorectomy or hysterectomy. For women not at high risk for these cancers, oophorectomy or hysterectomy should not be recommended for increasing the subsequent risk of CRC.