Discussion

This report indicates that the rate of new uterine cancer cases increased during 1999–2015, with larger increases observed among black, AI/AN, API, and Hispanic women than among white women. This contrasts with the recent decreases in incidence rates that have been observed for many cancer types, such as lung and colorectal cancers (1). One contributing factor to increasing uterine cancer incidence could be excess body weight; women who are overweight (body mass index [BMI] = 25.0–29.9 kg/m2) or have obesity (BMI ≥30 kg/m2) are approximately two to four times as likely to develop endometrial cancer as are women with healthy weight (4). During 2013–2016, approximately 40% of women in the United States had obesity, including 56% of black women and 49% of Hispanic women.*** The U.S. Preventive Services Task Force recommends that clinicians offer or refer adults with obesity to intensive, multicomponent behavioral interventions.††† Community-based strategies to promote healthy body weight include helping persons meet dietary and physical activity guidelines by supporting healthy eating and active living in such settings as communities, worksites, schools, and early care and education facilities (4). Other factors such as insufficient physical activity, increasing prevalence of diabetes, and decreasing use of estrogen plus progestin menopausal hormone therapy might also contribute to increases in endometrial cancer incidence (5).

This report also found that uterine cancer death rates were higher in 2016 than in 1999 and that black women were approximately twice as likely to die from uterine cancer as were women in other racial/ethnic groups. As with other cancers, the odds of surviving uterine cancer are much higher when it is detected at an early stage, when treatment is more effective (5). The 5-year relative survival estimate for localized uterine cancer is 80%–90% compared with <30% for distant uterine cancer (5). This report found that black women were more likely to receive a diagnosis at distant stage and with more aggressive histologic types than were other women, which might in part account for the higher death rate among black women.

Although population-based screening tests are recommended for several cancers, including breast, cervical, colorectal, and lung cancers, at present, population-based screening tests are not recommended for uterine cancer (6). An important early symptom of uterine cancer is abnormal vaginal bleeding, including bleeding between periods or after sex or any unexpected bleeding after menopause (i.e., any bleeding except intermittent bleeding within 1 year after cessation of menses or cyclic bleeding associated with use of cyclic postmenopausal hormone therapy) (3). Approximately 90% of women with uterine cancer report abnormal vaginal bleeding (6). A lower percentage of women with uterine sarcomas have abnormal vaginal bleeding (approximately 56%) or nonspecific symptoms, such as pelvic pain (22%); consequently, a higher percentage of sarcomas are not detected until the cancer has already spread (7). Uterine cancer outcomes could be improved by increasing awareness among women that abnormal vaginal bleeding should be evaluated promptly by a health care provider. It is also important for health care providers to perform timely evaluation and necessary follow-up of women’s concerns and symptoms (8). Transvaginal ultrasonography or endometrial tissue sampling are appropriate for initial evaluation of postmenopausal bleeding; further evaluation could include hysteroscopy combined with endometrial sampling (8). To help women make informed choices, health care providers can educate women about different procedural options (including surgical choices); discuss the benefits and risks of each procedure; and discuss the risk for cancer (9). CDC’s Inside Knowledge campaign attempts to raise awareness among women and health care providers about uterine cancer and other gynecologic cancers. Inside Knowledge uses a multimedia approach to ensure campaign messages reach the broadest audience possible.

The findings in this report are subject to at least five limitations. First, reporting of race and ethnicity uses data from medical records and death certificates, which might be inaccurate in some cases, especially among AI/AN; ongoing procedures are used to ensure that this information is as accurate as possible.§§§ Second, improved pathologic classification of tumors over time might influence rates and trends. Third, broad groups were used for histologic type, which might mask varying levels of tumor behavior. Fourth, in clinical practice, uterine cancers are commonly staged on the basis of histologic type using the International Federation of Gynecology and Obstetrics system (6); however, because this information is not routinely collected in cancer registries, this report used SEER Summary Stage to stage cancers. Finally, rate denominators were not adjusted for hysterectomy prevalence and might include women who did not have an intact uterus and were not at risk for uterine cancer, thus underestimating the actual rate among women at risk, particularly black women, who have higher rates of hysterectomy (10).

Multifactorial efforts at individual, community, clinical, and systems levels to help women achieve and maintain a healthy weight and obtain sufficient physical activity might reduce the risk for developing uterine cancer. Promoting awareness among women and health care providers of the need for timely evaluation of abnormal vaginal bleeding can increase the chance that uterine cancer is detected early and treated appropriately.