Relative Risk Of Endometrial Cancer Research Articles

Upper-Body Fat Distribution and Endometrial Cancer Risk

--To determine if body fat distribution affected endometrial cancer risk. --Case-control study. --This study was carried out at the H. Lee Moffitt Cancer Center at the University of South Florida, Tampa, where all patients in the case group received their diagnoses and histological confirmations. --Forty consecutive women newly diagnosed with endometrial cancer and 40 controls matched for age and Quetelet index. --Anthropometric measurements were taken for the abdomen, thigh, suprailiac, subscapular, biceps, and triceps skin fold thicknesses; waist and hip circumferences, weight, and height. Relative risks for endometrial cancer were calculated according to these anthropometric measurements. --Case patients with endometrial cancer had significantly greater waist-to-hip circumference ratios (P less than .001), abdomen-to-thigh skin fold ratios (P less than .01), and suprailiac-to-thigh skin fold ratios (P = .02) compared with control subjects matched for age and Quetelet index. The relative risk for endometrial cancer increased with an increasing waist-to-hip circumference ratio (less than or equal to 1.14 = 1.0; greater than 1.14 = 15.0), with an increasing abdomen-to-thigh skin fold ratio (less than or equal to 0.82 = 1.0; greater than 0.82 = 5.0), and with an increasing suprailiac to-thigh skin fold thickness ratio (less than or equal to 0.67 = 1.0; greater than 0.67 = 3.50). --Upper-body fat localization is a significant risk factor for endometrial cancer in women matched for age and Quetelet index.

Endometrial cancer and patterns of use of oestrogen replacement therapy; A cohort study : Br. J. Cancer; 59/3 (445–447)/1989

5,160 non-hysterectomised women aged 44-100 years completed a health survey questionnaire as part of a longitudinal study of a southern California retirement community begun in June 1981. As of 1 January 1987, 50 incident cancers of the endometrium had occurred among these women, who had contributed 23,786 years of follow-up. Women who had used oestrogen replacement therapy had a relative risk of endometrial cancer of 10 compared to women who had never used oestrogens (P less than 0.0001). Risk increased with increasing duration of use (chi 2 test for trend = 50.60, P less than 0.0001); women who had used oestrogens for 15 or more years had a relative risk of 20 (95% C.I. = 7.2, 54) compared to non-users. While current and recent users (i.e. those who had used oestrogen within one year of the initial survey) had the greatest risk (RR = 25, 95% C.I. = 9.2, 69), women who had last used oestrogens 15 or more years ago still had a significantly increased risk (RR = 5.8, 95% C.I. = 2.0, 17). No other variable studied had a major effect on risk, except smoking. Women who smoked at the time of menopause had a significantly reduced risk of disease (RR = 0.38, P = 0.005), which was essentially unchanged after adjustment for oestrogen use.

Endometrial cancer and patterns of use of oestrogen replacement therapy: a cohort study.

5,160 non-hysterectomised women aged 44-100 years completed a health survey questionnaire as part of a longitudinal study of a southern California retirement community begun in June 1981. As of 1 January 1987, 50 incident cancers of the endometrium had occurred among these women, who had contributed 23,786 years of follow-up. Women who had used oestrogen replacement therapy had a relative risk of endometrial cancer of 10 compared to women who had never used oestrogens (P less than 0.0001). Risk increased with increasing duration of use (chi 2 test for trend = 50.60, P less than 0.0001); women who had used oestrogens for 15 or more years had a relative risk of 20 (95% C.I. = 7.2, 54) compared to non-users. While current and recent users (i.e. those who had used oestrogen within one year of the initial survey) had the greatest risk (RR = 25, 95% C.I. = 9.2, 69), women who had last used oestrogens 15 or more years ago still had a significantly increased risk (RR = 5.8, 95% C.I. = 2.0, 17). No other variable studied had a major effect on risk, except smoking. Women who smoked at the time of menopause had a significantly reduced risk of disease (RR = 0.38, P = 0.005), which was essentially unchanged after adjustment for oestrogen use.

Postmenopausal estrogens in prevention of osteoporosis. Benefit virtually without risk if cardiovascular effects are considered

Postmenopausal estrogens can delay or prevent osteoporosis and decrease the frequency of fractures, but they also increase the risk of endometrial cancer. A decision analytic model was developed using a Markov process with 18 different states to estimate quality-adjusted life expectancy with and without estrogen therapy. The model considered fractures of the hip, wrist, pelvis, humerus and spine with potential outcomes of short-term morbidity, long-term disability, nursing home placement, and death. Quality adjustments were based on expert opinions. In sensitivity analyses, various risks of endometrial cancer and hysterectomy due to estrogens were examined. The effect of estrogen therapy on cardiac mortality also was considered. For a cohort of 50-year-old white women who would take estrogens for 15 years, the analysis showed a benefit of 0.47 years but 0.67 quality-adjusted years. For every five-fold increase in the relative risk of endometrial cancer, the benefit decreases by 0.07 quality years. The benefit would increase by 0.17 quality years for each 10 percent decrease in the fracture rate and 0.32 for each 10 percent decrease in cardiovascular mortality rate. Thus, estrogen therapy provides a significant gain in quality-adjusted life expectancy. In considering the efficacy of any drug, all the benefits of the drug as well as all its risks must be included. If the beneficial effect of estrogens on cardiovascular mortality is confirmed, it will overshadow all other effects. Any recommendation about postmenopausal estrogens with respect to osteoporosis that excludes their cardiovascular effects markedly underestimates the potential gains from therapy.

The risk of endometrial neoplasia and treatment with estrogens and estrogen-progestogen combinations. First results of a cohort study after one to four completed years of observation.

This prescription-based cohort investigation was undertaken in order to study whether climacteric estrogen treatment of women in a Swedish population might be associated with an increased risk of endometrial cancer, and whether added progestogens can afford any protection from developing estrogen-related endometrial neoplasia. Some 23 000 women who had been prescribed estrogens were followed up regarding the outcome of neoplastic lesions of the endometrium. The results are based on an observation period of one to four completed years, corresponding to 89 000 person-years. Among those cohort members exposed to estrogens alone, regardless of the duration, the relative risk of endometrial cancer was 1.3 (95% confidence interval 0.9 to 1.7). The inclusion of premalignant endometrial changes resulted in a significantly increased relative risk of 1.6 (1.2-2.1). The relative risk estimates in association with estrogen-progestogen combinations were 0.6 (0.2-1.4) for endometrial cancer and 0.8 (0.4-1.5) when including premalignant lesions. These data indicated a possible protective effect of progestogens against the development of endometrial neoplasia. It was concluded that estrogens were - within an observation period of 4 years - associated with an increased risk of premalignant endometrial lesions.

Endometrial Cancer, Epidemiology, and Medical Practice

The article by Hulka et al (p 475) in this issue ofThe JOURNALsuggests a halving of the relative risk of endometrial cancer in women, on reaching an average age of 50 years, who were taking a combination birth control pill at the time of the study. This is consonant with other reports that suggest a beneficial effect of progestins in moderating cancer risk from exogenous or endogenous estrogens. It is important to point out what the health care implications of such an observation might be for women in this age group. The data from this case-control study indicate what the relative benefit might be in reduction of endometrial cancer, but do not reveal the number of subjects at risk for such malignancy or the risk of oral contraceptive (OC) use that can be derived from a different type of epidemiological survey. The incidence of endometrial cancer in women

Exogenous estrogen and endometrial carcinoma: Case-control and incidence study

Recent independent case-control studies have indicated that treatment with exogenous estrogen is associated with an increase in the risk of endometrial cancer. This question was studied in Olmsted County, Minnesota, by identifying all cases of endometrial cancer among residents over a 30 year period (1945 through 1974) and by matching four controls to each of the 145 patients. The rate of past exposure to any exogenous estrogen for any duration was about the same for patients as for controls. However, the estimated relative risk of endometrial cancer associated with conjugated estrogen treatment of 6 months or longer was 4.9 (P < 0.01), and this increased to 7.9 (P < 0.01) with exposure for 3 years or longer. The risk increased with larger dose (1.25 mg. or more) and continuous administration of conjugated estrogens. The incidence of endometrial carcinoma over the three decades of the study, corrected for an increasing rate of hysterectomy, was constant. Thus to this time, the low rate of use of conjugated estrogens in this region over the past 30 years apparently has not had an appreciable impact on the incidence of endometrial cancer.