While several risk factors have been identified for uterine cancer, it is important to note that these factors do not always cause cancer. Many women have multiple risk factors and never develop cancer. On the other hand, some women with cancer have no known risk factors. Even if a woman with uterine cancer exhibits one or more risk factors, it is impossible to know which, if any, directly led to the development of her cancer.

Endometrial cancer risk factors

With all of that said, a woman’s risk of developing uterine cancer increases as she gets older, especially after age 60. One reason is the hormonal imbalances that occur after menopause. A shift in the delicate balance of estrogen and progesterone that is weighted more heavily toward estrogen can sometimes lead to abnormal cellular development in a woman’s uterine lining, or endometrium.

Some known uterine cancer risk factors involving changing estrogen levels include:

Estrogen therapy (given without corresponding levels of progesterone) – This treatment is sometimes prescribed to treat the symptoms of menopause, but it can increase a woman’s risk of uterine cancer since it increases the level of estrogen in the body.
High number of menstrual cycles – Women who have more menstrual cycles during their lifetimes have a higher risk of developing uterine cancer. This includes women who begin menstruating before age 12, women who experience menopause after age 55 and women who have never been pregnant. On the other hand, the use of oral contraceptives can lower that risk by suppressing ovulation and reducing a woman’s estrogen exposure.
Excess weight and obesity – Fatty tissue in overweight women can produce excess estrogen, and the risk of uterine cancer has been found to rise along with increases in body mass.
Ovarian tumors – A specific type of ovarian tumor, the granulosa-theca cell tumor, can produce estrogen and stimulate the endometrium.

Tamoxifen and endometrial cancer

Another risk factor for endometrial cancer is the use of tamoxifen, a selective estrogen receptor modulator (SERM) that’s commonly used to treat hormone receptor-positive breast cancer in both men and women. In some cases, it may also be prescribed to help prevent breast cancer in women with a higher-than-average risk of developing the malignancy.

Although tamoxifen can act as an anti-estrogen in breast tissue, it may act as an estrogen within the uterus. And, as was noted above, abnormally high estrogen levels can be a uterine cancer risk factor. Indeed, many studies have shown that when compared to an age-matched population, women who take tamoxifen have a two to three times higher relative risk of developing endometrial cancer.

PCOS and endometrial cancer

Polycystic ovary syndrome (PCOS)—a relatively common condition characterized by the imbalance of reproductive hormones in women—can also be an endometrial cancer risk factor. Because PCOS can cause a woman to have higher levels of estrogen and lower levels of progesterone, it can increase her chances of developing uterine cancer.

Lynch syndrome and endometrial cancer

Lynch syndrome (also known as hereditary nonpolyposis colorectal cancer) is an inherited condition characterized by mutations in genes that would normally protect someone from developing certain malignancies. This syndrome is the most common cause of hereditary colorectal (colon) cancer, but it can also significantly increase the risk of developing uterine cancer and numerous other malignancies. In fact, studies show that the lifetime risk of endometrial cancer in individuals with Lynch syndrome is 60%.

The provider to choose for uterine cancer diagnosis and treatment

Moffitt Cancer Center, the only National Cancer Institute-designated Comprehensive Cancer Center based in Florida, continues to lead the way in researching risk factors that can cause healthy endometrial cells to become cancerous. We are proud to offer our patients the latest options in the screening, diagnosis and treatment of uterine cancer in a single location, and all without the need for a referral.

For more information about uterine cancer risk factors, please call 1-888-663-3488 or schedule an appointment using our convenient new patient registration form. The team at Moffitt knows how stressful it can be to wait for a uterine cancer diagnosis, especially if you have one or more endometrial cancer risk factors present, so we will be sure to connect you to a cancer expert as soon as possible.