A one to two-year course of tamoxifen approximately doubles the risk of endometrial cancer, and a five-year course of therapy quadruples that risk. Raloxifene, a similar drug, did not raise the risk of endometrial cancer. Previously having ovarian cancer is a risk factor for endometrial cancer, as is having had previous radiotherapy to the pelvis. Specifically, ovarian granulosa cell tumors and thecomas are tumors associated with endometrial cancer. Low immune function has also been implicated in endometrial cancer. High blood pressure is also a risk factor, but this may be because of its association with obesity. Sitting regularly for prolonged periods is associated with higher mortality from endometrial cancer. The risk is not negated by regular exercise, though it is lowered. Protective factors
Smoking and the use of progestin are both protective against endometrial cancer. Smoking provides protection by altering the metabolism of estrogen and promoting weight loss and early menopause. This protective effect lasts long after smoking is stopped. Progestin is present in the combined oral contraceptive pill and the hormonal intrauterine device (IUD). Combined oral contraceptives reduce risk more the longer they are taken: by 56% after four years, 67% after eight years, and 72% after twelve years. This risk reduction continues for at least fifteen years after contraceptive use has been stopped. Obese women may need higher doses of progestin to be protected. Having had more than five infants (grand multiparity) is also a protective factor, and having at least one child reduces the risk by 35%.
Pre-cancerous endometrial hyperplasias are also referred to as endometrial intraepithelial neoplasia. Mutations in the KRAS gene can cause endometrial hyperplasia and therefore Type I endometrial cancer. Endometrial hyperplasia typically occurs after the age of 40. Endometrial glandular dysplasia occurs with an overexpression of p53, and develops into a serous carcinoma. Diagnosis
Diagnosis of endometrial cancer is made first by a physical examination, endometrial biopsy, or dilation and curettage (removal of endometrial tissue; D&C). This tissue is then examined histologically for characteristics of cancer. If cancer is found, medical imaging may be done to see whether the cancer has spread or invaded tissue. Examination
Routine screening of asymptomatic people is not indicated since the disease is highly curable in its early, symptomatic stages. Instead, women, particularly menopausal women, should be aware of the symptoms and risk factors of endometrial cancer. A cervical screening test, such as a Pap smear, is not a useful diagnostic tool for endometrial cancer because the smear will be normal 50% of the time. A Pap smear can detect disease that has spread to the cervix. Results from a pelvic examination are frequently normal, especially in the early stages of disease. Changes in the size, shape or consistency of the uterus or its surrounding, supporting structures may exist when the disease is more advanced.