Risk Factor For Uterine Cancer Research Articles

Hormone Replacement Therapy and Risks of Various Cancers in Postmenopausal Women with De Novo or a History of Endometriosis.

This study examined the impact of hormone replacement therapy (HRT) on the occurrence of various cancers in postmenopausal women with de novo or a history of endometriosis. In the datasets for ten cancers (cervical, uterine, ovarian, breast, colon, gastric, liver, lung, pancreatic, and thyroid), women who received HRT (the HRT group) and those who did not (the control group) were selected by a 1:1 matching with those who met the study criteria. In the dataset for each cancer, the incidence of each cancer was very low (0.2% to 1.5% in the HRT group and 0.2% to 1.3% in the control group). The duration of HRT was 1.3 ± 2.1 years. After adjusting for co-variables, HRT was a significant risk factor for uterine cancer (p < 0.05). However, the risk of liver cancer decreased significantly with duration of HRT (p < 0.05). Moreover, combined estrogen and progesterone decreased the risks of liver and thyroid cancers significantly (p < 0.05), and estrogen alone decreased the risks of breast and lung cancers significantly (p < 0.05). Tibolone was not associated with the risk of any of the cancers assessed. These results can help guide the use of HRT in women with de novo or a history of endometriosis.

Hair relaxer use and risk of uterine cancer in the Black Women's Health Study

BackgroundChemical hair relaxers, use of which is highly prevalent among Black women in the US, have been inconsistently linked to risk of estrogen-dependent cancers, such as breast cancer, and other reproductive health conditions. Whether hair relaxer use increases risk of uterine cancer is unknown. MethodsIn the Black Women's Health Study, 44,798 women with an intact uterus who self-identified as Black were followed from 1997, when chemical hair relaxer use was queried, until 2019. Over follow-up, 347 incident uterine cancers were diagnosed. We used multivariable Cox proportional hazards regression models, adjusted for age and other potential confounders, to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations of hair relaxer use with risk of uterine cancer. ResultsCompared to women who never used hair relaxers or used them infrequently (<4 years and ≤1–2 times/year), the HR for uterine cancer associated with heavy use (≥15 years and at least 5 times/year) was 1.18 (95% CI: 0.81, 1.71). However, among postmenopausal women, compared to never/light use, the HR for moderate use was 1.60 (95% CI: 1.01, 2.53), the HR for heavy use was 1.64 (1.01, 2.64), and the HR for ≥20 years of use regardless of frequency was 1.71 (1.08, 2.72). Results among premenopausal women were null. ConclusionsIn this large cohort of Black women, long-term use of chemical hair relaxers was associated with increased risk of uterine cancer among postmenopausal women, but not among premenopausal women. These findings suggest that hair relaxer use may be a potentially modifiable risk factor for uterine cancer.

Epidemiological characteristics of endometrial cancer patients treated at a tertiary health center in National Capital Territory of India

A retrospective study which analyzed the data of female patients attending a tertiary care center in National Capital Territory for the treatment of endometrial cancer. Eighty-six histopathologically confirmed cases of carcinoma endometrium were taken from January 2016 to December 2019. Detailed information was collected regarding patient's case history, sociodemographic data (age of presentation, occupation, religion, residence, and substance addiction), clinical presentation, diagnostic and therapeutic procedures, and known risk factors (age at menarche and menopause, parity, obesity, use of oral contraceptive pills, hormone replacement therapy, and comorbidities such as hypertension and diabetes). After analysis, results were presented as mean ± standard deviation and frequency. Eighty-six percent of the patients (n = 73) were in the age group of 40-70 years; the mean age of the patients at diagnosis of endometrial cancer was 54 years. Eighty-one percent (n = 70) of the patients were from urban areas. Sixty-seven percent of the females (n = 54) were Hindu. All the patients were housewives with nonsedentary lifestyles. Most patients (88%; n = 76) presented with bleeding per vaginum. Fifty-nine percent (n = 51) had stage I disease, followed by 15% (n = 13) with stage II, 14% (n = 12) with stage III, and 12% (n = 10) with stage IV disease. Eighty-two percent (n = 72) of the patients had endometrioid carcinoma. Other less common variants were mixed Mullerian malignant tumor, squamous, adenosquamous, serous, and endometrioid stromal. Forty-four percent (n = 38), 39% (n = 34), and 16% (n = 14) of the patients had grade I, grade II, and grade III tumor, respectively. 53.5% of the cases (n = 46) had >50% myometrial invasion at the time of presentation. Eighty-two percent (n = 71) of the patients were postmenopausal. The mean age at menarche and menopause was 13 years and 47 years, respectively. Fifteen percent (n = 13) of the females were nulliparous. Forty-six percent (n = 40) of the patients were overweight. Most patients (82%) had no history of addiction. Twenty-five percent (n = 22) of the patients had hypertension, and 27% (n = 23) has diabetes as comorbidity. The incidence of endometrium cancer is showing a steady rise in the recent past. Early age of menarche, late age of menopause, nulliparity, obesity, and diabetes mellitus are well-documented risk factors for uterine cancer. Better outcome and control of disease is possible by understanding of endometrial cancer etiology, risk factors, and its preventive measures. Thus, a robust screening program is warranted to detect the disease in early stage and for increased survival.

Age Specific Risks of Uterine Cancer in Type 2 Diabetes and Associated Comorbidities in Taiwan.

Simple SummaryThe incidence of uterine cancer is increasing worldwide in recent decades, especially in the young age population. In parallel, a trend of early onset of diabetes mellitus (DM) and obesity was also observed in the young population. Since DM and obesity are known risk factors of uterine cancer, we proposed to investigate the age-specific risks of uterine cancer in subjects with DM and related metabolic comorbidities. In this nationwide population-based study, we found the risk of uterine cancer in DM subjects was significantly higher in the younger age groups, especially in the age group 30–39 years. Obesity, polycystic ovarian syndrome, hyperlipidemia, statin use, and hormone replacement therapy were also significantly associated with uterine cancer in subjects younger than 50 years of age. Therefore, subjects with DM, especially younger women with respective comorbidities, should be recommended to have appropriate uterine cancer screenings for early detection.Introduction: The global incidence of uterine cancer has increased substantially in recent decades. We evaluated if the trend of increasing prevalence of diabetes mellitus (DM) and obesity are attributed to the development of uterine cancer. Methods: Using data derived from the National Health Insurance database and Taiwan Cancer Registry, multivariate Cox proportional hazards regression models were adapted to analyze the risk factors of uterine cancer with potential confounding variables. Results: There were a total of 5,104,242 women aged 30–70 years enrolled in the study and 147,772 of them were diagnosed with DM during 2005–2007. In a total of 11 years of follow-up, 14,398 subjects were diagnosed with uterine cancer. An elevated risk of uterine cancer was observed in women with DM of all ages (HR 1.66, 95% CI 1.53–1.81, p < 0.0001). The effect of DM was highest at age 30–39 years (RR 3.05, 95% CI 2.35–3.96, p < 0.0001). In the group of <50 years old, DM patients had at least a twofold higher risk of developing uterine cancer (HR 2.39, 95% CI 2.09–2.74, p < 0.0001). Subjects among all ages diagnosed with polycystic ovary syndrome (PCOS) (HR 2.91, 95% CI 2.47–3.42, p < 0.0001), obesity (HR 2.13, 95% CI 1.88–2.41, p < 0.0001), and those undergoing hormone replacement therapy (HRT) (HR 1.60, 95% CI 1.33–1.93, p < 0.0001) were also positively associated with uterine cancer. Positive associations of hyperlipidemia (HR 1.33, 95% CI 1.22–1.46, p < 0.0001) and statin use (HR 1.27, 95% CI 1.12–1.44, p = 0.0002) on uterine cancer were only observed in subjects <50 years. On the contrary, hyperlipidemia was negatively associated with uterine cancer in subjects ≥50 years (HR 0.91, 95% CI: 0.84–0.98, p = 0.0122). Conclusions: DM is in general the most important risk factor for uterine cancer, especially in premenopausal women. Obesity, PCOS, HPL, statin use, and HRT were also associated with uterine cancer in subjects younger than 50 years. Premenopausal women with DM and respective comorbidities should be aware of the development of uterine cancer.

Assisted reproductive technology and uterine cancer risk. A systematic review and meta-analysis

BACKGROUND: The problem of infertility has not only medical, but also socio-demographic significance. To date, the global scale of the spread of various forms of infertility is beyond doubt among specialists around the world. This, in turn, causes an increase in the frequency of prescribing assisted reproductive technologies, but the question of the relationship between the prescribing of drugs used to treat infertility and the risk of developing cancer of the uterine body remains poorly understood.&#x0D; AIM: The aim of this study was to assess the possible relationship between in vitro fertilization, the use of ovulation stimulation drugs and the risk of developing uterine cancer in women with infertility.&#x0D; MATERIALS AND METHODS: This literature systematic review is based on resources from the following databases: Medline, ClinicalKey, Google Scholar, Embase, the Cochrane Library, and eLIBRARY for the period 19992022. The search for publications was carried out using keywords defined in accordance with the PICO principle (P, population or patients; I, intervention; C, comparison; O, outcomes): female, women, infertility, infertility treatment, in vitro fertilization, IVF, assisted reproductive technology, ART, ovarian stimulation, ovarian hyperstimulation, clomiphene citrate, hCG, hMG, tamoxifen, uterine, endometrial, cancer, carcinoma neoplasm, uterine neoplasm. The following SQL operators were used during the search: AND and OR.&#x0D; RESULTS: The search resulted in 37 representative publications, with eight studies selected for meta-analysis.&#x0D; CONCLUSIONS: This systematic review and meta-analysis have demonstrated the ambiguity of the design and results of studies on the possible relationship of uterine cancer and assisted reproductive technology methods published to date. The issue under review is urgent due to the high frequency of infertility and an increase in the frequency of gynecologic cancers. The conducted studies confirm that it is impossible to evaluate the carcinogenic effect of ovulation inducers or in vitro fertilization methods without adjusting for the infertility factor, as well as risk factors for uterine cancer. There is still a high need for further research, particularly for studying the safety profile of infertility treatment methods in relation to long-term cancer risks.

Long-term risk of uterine malignancies in women with uterine fibroids confirmed by myomectomy: a population-based study

Leiomyosarcomas may originate from pre-existing uterine fibroids. However, recent studies showed that leiomyosarcomas do not arise from malignant changes in fibroids. Epidemiological data on the long-term risk of uterine malignancy with uterine fibroids are lacking. We aimed to determine whether uterine fibroids are a risk factor for uterine cancer. Patient data (2007–2020) from the Korean Health Insurance program were obtained. Using the procedure and diagnostic codes, data from patients who underwent myomectomy and appendicitis (control group) were extracted Using 1:1 propensity-score matching, 84,507 women were each allocated to the uterine fibroids and control groups. Endometrial cancer occurred in 36 44 and 44 36 women in the uterine fibroids and control groups (p = .371), respectively; 6/36 46 and 4 5/44 37 cases of uterine corpus cancer sarcoma occurred in the respective groups. Total uterine cancer (excluding cervical cancer) occurred in 46 and 39 37patients in the uterine fibroids and control groups, respectively (p = .323). A higher risk of uterine malignancy was not found in women with uterine fibroids confirmed by myomectomy. If surgery is indicated, a myomectomy can be safely performed without increasing the cancer risk. IMPACT STATEMENT What is already known on this subject? Traditionally, leiomyosarcomas were considered to originate from pre-existing uterine fibroids. However, recent studies suggest that leiomyosarcomas do not arise from the malignant change of fibroids. Meanwhile, there is a dearth of real-world evidence on the risk of uterine cancer in patients with uterine fibroids. What do the results of this study add? No evidence of a higher risk of uterine malignancy was found in women having uterine fibroids confirmed by myomectomy in this population-based study. In our cohort of women with uterine fibroids, tissue injury by myomectomy does not appear to cause malignant transformation. What are the implications of these findings for clinical practice and/or further research? Uterine fibroids doesn’t appear to be a risk factor for uterine malignancies, and tissue injury by myomectomy does not appear to cause malignant transformation. If surgery is indicated, myomectomy can be performed safely, given that the long-term risk of uterine malignancy does not increase.

Lymphovascular space invasion as an independent predictor of lymph node status at a single academic institution

Objective: The treatment of uterine cancer is largely determined by stage and prognostic factors. Lymphovascular space invasion (LVSI) is considered a risk factor for uterine cancer, but it is currently not classified as an independent predictor for lymph node status. This has been suggested in prior studies, but given variations in the pathologic diagnosis of LVSI among pathology departments, it has been difficult to prove. Our objective was to review all uterine cancer cases at a single academic institution to determine whether LSVI can serve as an independent predictor of lymph node status.

No. 366-Gynaecologic Management of Hereditary Breast and Ovarian Cancer.

This Committee Opinion outlines the gynaecologic management recommendations for women diagnosed with hereditary breast and ovarian cancer syndrome (HBOC) with respect to screening, contraception, chemoprophylaxis, fertility considerations, risk-reducing surgery, and post-oophorectomy care. This Committee Opinion is designed for gynaecologic oncologists, general gynaecologists, family physicians, genetic counsellors, registered nurses, nurse practitioners, residents, and health care providers. Adult women (18 years and older) with a pathogenic germline variant in the BRCA1, BRCA2, and other ovarian cancer-associated genes. While reviewing evidence, databases searched include Medline, Cochrane, and PubMed. Medical Subject Heading search terms used include BRCA AND gynaecology management, hormone replacement therapy, risk reduction, chemoprophylaxis, fertility from 01/2010 and 10/2017. Literature search was begun 07/2017 and finalized 10/2017. In total 183 studies were identified, and 101 were used. The content and recommendations were drafted and agreed upon by the principal authors. The Board of the Society of Obstetricians and Gynaecologists of Canada approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology framework (Table 1). The interpretation of strong and conditional (weak) recommendations is described in Table 2. The Summary of Findings is available upon request. We may expect a risk reduction of up to 90% in women predisposed to HBOC who undergo risk-reducing bilateral salpingo-oophorectomy. The harms of iatrogenic premature menopause are offset by the benefits of risk reduction. By minimizing potential tubal/ovarian/peritoneal cancers, we can expect savings to the health care system. Evidence will be reviewed 5 years after publication to decide whether all or part of the opinion should be updated. However, if important new evidence is published prior to the 5-year cycle, the review process may be accelerated for a more rapid update of some recommendations. This guideline was developed with resources funded by the Society of Obstetricians and Gynaecologists of Canada.

THYROID HORMONES (T3 AND T4) AS A MARKER OF UTERINE CANCER RISK FACTOR AFTER MENOPAUSE

Due to limited available information of the correlation between T3 and T4 on uterine cancer. This study focused on the following: Possibility of T3 and T4 as a marker of uterine cancer by studying the relationship between T3 and T4 and uterine cancer through a hormonal parameters. The study included collection of samples attending the Hospitals in Mosul, divided to two groups (40 healthy women and 35 women diagnosed with uterine cancer only). Each patient was evaluated clinically and by a biochemical laboratory tests, which include estrogen, progesterone, T3, T4, adiponectin and BMI in serum. The results showed that T3 and T4 may increases the incidence of uterine cancer especially after menopause because its increase significantly BMI and estrogen and decreased adiponectin lead to disorder in hormonal imbalance in women body. Novel of this research showed that thyroid hormones are a new risk factor for uterine cancer especially after menopause. Accordingly, women should pay attention for the level of thyroid hormones during menopausal age to reduce the risk of uterine cancer.

Perceptions of obesity and cancer risk in female bariatric surgery candidates: Highlighting the need for physician action for unsuspectingly obese and high risk patients

ObjectivesTo determine: 1) whether obese women perceive themselves to be obese or at risk for malignancy, 2) perceived impact of obesity on cancer risks, 3) compliance with cancer screening, and 4) rates of menstrual dysfunction. MethodsSurveys were administered to female patients presenting for bariatric weight loss surgery. Demographics, gynecologic history, perception of cancer risk, and screening history were collected/analyzed. Women were categorized as obese (BMI: 30–39kg/m2), morbidly obese (40–49kg/m2), super obese (≥50kg/m2) and compared. ResultsNinety-three women (mean age: 44.9years, mean BMI: 48.7kg/m2) participated and 45.7% felt they were in ‘good’, ‘very good’, or ‘excellent’ health despite frequent medical comorbidities. As BMI increased, women were more likely to correctly identify themselves as obese (23% of obese vs. 77% of morbidly obese vs. 85% of super obese; p<0.001) but there were no significant differences in comorbidities. Two-thirds of women correctly identified obesity as a risk factor for uterine cancer, yet 48% of those retaining a uterus perceived that it was “not likely/not possible” to develop uterine cancer. Menstrual irregularities were common as was evaluation and interventions for the same; 32% had prior hysterectomy. Participation in cancer screening was robust. ConclusionsWomen presenting for bariatric surgery have high rates of menstrual dysfunction. While they perceive that obesity increases uterine cancer risk, they often do not perceive themselves to be at risk. This disconnect may stem from the fact that many failed to identify themselves as obese perhaps because overweight/obesity has become the norm in U.S. society.

OSTEOPOROSIS AS A NOVEL MARKER OF UTERINE CANCER RISK FACTOR

Due to limited available information on the occurrence and treatment of uterine cancer, health institutions in major countries trend to study some factors and diseases that may relation or plays as predisposing factors of the occurrence of uterine cancer and the lack of previous studies on the impact of osteoporosis on the incidence of uterine cancer and the rapid spread of uterine cancer in recent years all over the world and till know the exact mechanism is not fully clear. This study focused on the following: possibility of osteoporosis as a marker of uterine cancer by studying the relationship between osteoporosis and uterine cancer through a biochemical and hormonal parameters responsible for osteoporosis and its effect on uterus and possibility of malignant changes. The study included collection of samples attending the Hospitals in Mosul, from 82 women had no uterine cancer and divided to two groups (44 healthy women and 38 women diagnosed as osteoporosis only) and 101 women with uterine cancer (43 with uterine cancer only and 58 women are associated osteoporosis with uterine cancer dose not received any treatment for their condition). Each patient was evaluated clinically and by a biochemical laboratory tests, which include phosphorus, calcium, vitamin D3, alkaline phosphatase ALP, estrogen and progesterone in serum by using commercial kits. The results showed the osteoporosis may increases the incidence of uterine cancer. Novel of this research showed that Osteoporosis is a new risk factor for uterine cancer. Accordingly, women should pay attention for her bone health and early diagnosis and treatment of osteoporosis to prevent and reduce the risk of uterine cancer.

STK15 F31I polymorphism is associated with increased uterine cancer risk: A pilot study

Objective. STK15 is a serine threonine kinase which assists chromosomal separation and mitotic spindle stability through interaction with the centrosome during mitosis. We hypothesized that STK15 polymorphisms might modulate the risk of uterine cancer. Methods. We used a hospital-based case–control study to assess the association between STK15 polymorphisms and risk of uterine cancer. Cases and controls were matched on age, race, and smoking status. Two common STK15 single nucleotide polymorphisms (SNPs), F31I (T/A), and V57I (G/A), were genotyped. Odds ratios (OR) and 95% confidence intervals (CI) were obtained using unconditional logistic regression analysis. Results. A total of 193 women with uterine cancer and 218 controls were genotyped for both SNPs. After adjustment for age, race, and smoking status for the F31I SNP, the homozygous variant genotype (AA) was associated with a significantly increased uterine cancer risk (OR 10.2; 95% CI 2.23–46.5). Individuals with the heterozygous genotype (TA) and a history of tobacco use also exhibited an increased risk for uterine cancer (OR 2.63; 95% CI 1.20–5.76). For the V57I SNP, neither the homozygous (AA) nor the heterozygous (GA) variant genotypes were associated with significantly altered risk for uterine cancer (OR 0.76; 95% CI 0.18–3.25 and OR 0.88; 95% CI 0.52–1.49). Conclusion. Our study demonstrates that STK15 F31I SNP is associated with an increased risk for uterine cancer. Confirmation of this pilot study is needed in a larger case–control population to evaluate this genetic variant with other known risk factors for uterine cancer.

STK15 F31I polymorphisms and uterine cancer risk: A case-control analysis

5511 Background: STK15 is a serine threonine kinase which assists chromosomal separation and mitotic spindle stability through interaction with the centrosome during mitosis. STK15 polymorphisms have been associated with an increased risk for breast cancer in several case-control studies. We hypothesized that STK15 polymorphisms might modulate risk of uterine cancer. Methods: Uterine cancer patients treated at M. D. Anderson Cancer Center were identified from the tumor bank database from January 1, 2000 to June 30, 2006. Two common STK15 single nucleotide polymorphisms (SNPs), F31I (T/A) and V57I (G/A), were genotyped in patients with uterine cancer and in a control population matched for age, race, and smoking status. Odds ratios (OR) and 95% confidence intervals (CI) were obtained using unconditional logistic regression analysis. Results: A total of 193 women with uterine cancer and 218 controls were genotyped for both SNPs. After adjustment for age, race, and smoking status for the F31I SNP, the homozygous variant genotype (AA) was associated with a significantly increased uterine cancer risk (OR 10.2; 95% CI 2.23–46.5). Individuals with the heterozygous genotype (TA) and a history of tobacco use also exhibited an increased risk for uterine cancer (OR 2.63; 95% CI 1.20–5.76). For the V57I SNP, neither the homozygous (AA) nor the heterozygous (GA) variant genotypes were associated with significantly altered risk for uterine cancer (OR 0.76; 95% CI 0.18–3.25 and OR 0.88; 95% CI 0.52–1.49). Conclusions: Our study demonstrates that STK15 F31I SNP is associated with an increased risk for uterine cancer. Confirmation of this pilot study is needed in a larger case-control population to evaluate this genetic variant with other known risk factors for uterine cancer. No significant financial relationships to disclose.

Awareness of general and personal risk factors for uterine cancer among healthy women

Participation rates in gynaecological cancer screening are influenced by different factors. The knowledge of general and personal risk factors for uterine cancer among women might influence their interest in gynaecological cancer screening. Two thousand nine hundred women in 23 gynaecological outpatient services were invited to answer a structured questionnaire regarding general and personal risk factors for cervical and endometrial carcinoma; 2108 women participated. Women with a history of cancer were excluded from the study. It was found that levels of knowledge about uterine carcinoma were low. Only 47.4% of women knew the difference between the sites of origin of cervical and endometrial cancer. Seventy-seven per cent of participants assessed their knowledge about uterine malignancies as insufficient; 96.3% would appreciate more information about uterine cancer. Younger women were significantly less well informed than postmenopausal women. Known risk factors such as smoking or human papillomavirus (HPV) infection as factors for cervical cancer were underestimated; most women assessed genetic factors as most important for the development of uterine cancer. The level of information about risk factors as well as general facts about gynaecological cancer in women is low. Ameliorating this lack of information might influence the perception of uterine cancer and result in higher participation rates in gynaecological cancer screening.

Adenomyosis as an optional risk factor for uterine cancer

The problem of adenomyosis malignization is controversial and insufficiently explored. Rate of the malignant transformation of adenomyosis varies from O.l to 24 per cent; as a rule, malignization of the stromal component of adenomyosis is described, works containing cancerous transformation description are isolated ones. Comparative clinical and morphological and immunohistochemical investigation of the cancerous transformation of adenomyosis (6 observations), endometrium cancer in combination with adenomyosis (16 observations), and typical adenomyosis (9 observations) is carried out. Obtained data indicate the precancerous optional significance of adenomyosis, risk of which increases in senior age groups. Endometrial adenocarcinoma does not exhibit a tendency to invasive growth into adenomyosis nidi; combined independent development of endometrium cancer and adenomyosis malignization with exo- and endophyte growth is possible, which determines the hypodiagnostics of malignizated adenomyosis. Morphological verification of malignizated adenomyosis demands comprehensive clinical and morphological investigation with broad study of operating material and with taking into consideration the stages of cancerous transformation morphogenesis established during the work. Late diagnostics and inadequate surgical treatment diagnose the unfavorable prognosis.

Cancer incidence in a cohort of infertile women.

To explore further the relation between infertility and breast and female reproductive cancers, cancer incidence among 2,632 Israeli women treated for infertility between 1964 and 1974 was evaluated. Cancer incidence through December 1981 was determined by matching the study cohort to the Israel Cancer Registry. The observed number of cancers was compared with sex-age-ethnic and calendar-year, site-specific national cancer rates. There were 42 cancers observed compared with 37.4 expected, yielding a standardized incidence ratio of 1.1 (95% confidence interval (CI) = 0.8-1.5). Analysis by infertility diagnosis demonstrated no significant excess of total cancer incidence; the standardized incidence ratio was 1.3 (95% CI = 0.8-1.8) for infertility due to hormonal deficiency, 0.7 (95% CI = 0.3-1.4) for mechanical infertility, 1.6 (95% CI = 0.6-3.6) for infertility of the male partner, and 1.1 (95% CI = 0.5-2.2) for unclassified diagnosis. Site-specific analyses revealed a significantly increased risk (8.0; 95% CI = 2.5-19.3; four cases observed, 0.50 expected) of endometrial cancer for the hormonal group and a nonsignificant excess of breast cancer and melanoma. Although numbers were small, women with disorders causing unopposed estrogen production had a risk of 1.4 (95% CI = 0.8-2.2) for all cancer sites, which reached 10.3 (95% CI = 2.6-28.2; three cases observed, 0.29 expected) for endometrial cancer and 1.8 (95% CI = 0.8-3.4; eight cases observed, 4.43 expected) for breast cancer. Among women with nonhormonal infertility, there was a suggestion of increased risks of carcinoma of the ovary (3.2; 95% CI = 0.3-32.9; two cases observed, 0.63 expected) and thyroid (3.0; 95% CI = 0.3-24.6; two cases observed; 0.67 expected). No evidence of an association between ovulation-inducing drugs and cancer was found. This study supports the hypothesis that infertility caused by hormone deficiency is a risk factor for uterine cancer, but is inconclusive regarding breast cancer.