1. Guidelines for Screening
There is no evidence to suggest that screening women prior to or during estrogen-progestin therapy, also known as hormone therapy, would decrease endometrial cancer mortality. Women on hormone therapy should have a prompt diagnostic work-up for abnormal bleeding. Although women using certain hormone regimens have an increased risk of endometrial cancer, most women who develop cancer will have vaginal bleeding. There is no evidence that screening these women would decrease mortality from endometrial cancer.
Hereditary Nonpolyposis Colorectal Cancer
The lifetime risk of endometrial cancer for women with hereditary nonpolyposis colorectal cancer (HNPCC) and for women who are at high risk for HNPCC is as high as 60%. These cases are often diagnosed in the fifth decade, 10 to 20 years earlier than sporadic cases. Because the risk of endometrial cancer is so high among these women, international guidelines suggest gynecologic surveillance including annual transvaginal ultrasound with endometrial biopsy for women aged 25 to 35 years.
The risk of endometrial cancer is increased in women who are treated with tamoxifen and is even greater in the subset of women who have a history of prior estrogen therapy. Beyond a routine gynecologic examination eliciting any history of abnormal bleeding, it has been recommended that screening studies and procedures for detecting endometrial pathology in women taking tamoxifen should be left to the discretion of the individual gynecologist. Commonly, there are endometrial abnormalities in women taking tamoxifen, especially in false-positive endovaginal ultrasound screening tests. More importantly, any abnormal uterine bleeding should be completely evaluated.
To date, there have been no published studies evaluating the effect of endometrial cancer-screening modalities on mortality among women taking tamoxifen for breast cancer treatment or prevention.
Evidence of Harms
Abnormal ultrasound typically requires further investigation including endometrial biopsy (sampling) may result in discomfort, bleeding, infection, and rarely uterine perforation. Endometrial sampling by hysteroscopic biopsy carries a 0.13% rate of complications. Discomfort occurs in 16% with hysteroscopic biopsy and 10% with blind biopsy. Risks associated with false-positive test results include anxiety and additional diagnostic testing and surgery. Endometrial cancers may be missed on endometrial sampling and ultrasound.
There is no evidence that screening by ultrasonography (e.g., endovaginal ultrasound or transvaginal ultrasound) reduces mortality from endometrial cancer. Most cases of endometrial cancer (85%) are diagnosed at low stage because of symptoms, and survival rates are high.
Screening is not recommended
2. Cancer Prevention
There is no known means of preventing endometrial cancer. The use of unopposed estrogen should be avoided.
© Strang Cancer Prevention Institute