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Introduction to Uterine Cancer

Uterine cancer arises in the uterus, a hollow, pear-shaped female organ where the baby grows. Uterine cancer includes endometrial cancer, uterine sarcomas, and placental cancer. Endometrial cancer happens when cancer begins in the tissue lining the uterus (endometrium). Uterine sarcomas occur when cancer grows in the muscles or other supporting tissues in the uterus; uterine sarcoma accounts for only a small portion of cancers of the uterus. Placental cancer is a rare type of cancer that affects placenta, the vascular organ that connects the fetus and the mother's uterus.

Endometrial cancer is also called adenocarcinoma of the endometrium/uterus, endometrial/uterine adenocarcinoma, and uterine cancer. Endometrial cancer is the most common type of uterine cancer. Although the exact cause of endometrial cancer is unknown, increased levels of estrogen appear to have a role. The incidence of endometrial cancer in women in the U.S. is 1% to 2%. The incidence peaks between the ages of 60 and 70 years, but 2% to 5% of cases may occur before the age of 40 years.

Placental cancer is also called choriocarcinoma. Placental cancer originates in trophoblastic cells of the placenta (afterbirth). The technical term given to the abnormal growth of trophoblastic cells is gestational trophoblastic neoplasia. Gestational trophoblastic neoplasia is classified into three types:

  1. Hydatiform mole, which stays in the uterus.
  2. Invasive hydatiform mole, which invades locally.
  3. Choriocarcinoma, which is the gravest and may spread throughout the body.