– Adenocarcinomas account for most endometrial cancer; other tumor types include adenoacanthoma and clear cell and squamous cell tumors.
Causes and Incidence
The cause of endometrial cancer has not yet been firmly established although a long-established link exists to hormone-related disorders. However, approximately 40% of endometrial tumors appear to be autonomous with no known etiology. Associated risk factors include adenomatous hyperplasia of the endometrium, menstrual irregularities, delayed menopause, infertility, diabetes or hypertension, and a history of breast or ovarian cancer.
Endometrial cancer is the most common of the gynecologic malignancies, with more than 31,000 new cases a year in the United States. This cancer is found primarily in postmenopausal women between 55 and 60 years of age. The women tend to be from highly industrialized countries, and the prevalence has increased sharply.
Cells begin as endometrial hyperplasia and change to cancer cells, beginning in the fundus of the uterus and spreading to the entire endometrium. The tumor may then extend down the endocervical canal and involve the cervix and vagina. It also spreads through the uterine wall to the abdominal cavity and adjacent structures and metastasizes to the pelvic and paraaortic lymph nodes, lungs, bone, and brain.
The only significant clinical sign of endometrial cancer is inappropriate uterine bleeding. Approximately one third of postmenopausal women who experience such bleeding have endometrial cancer.
Advanced disease leads to complications such as bowel obstruction, ascites, and respiratory distress, and the prognosis is poor.
A Papanicolaou smear is helpful but undependable, because 30% to 40% of smears yield false-negative results. Malignant cells on endometrial biopsy and fractional curettage yield a definitive diagnosis.
Chemotherapy for recurrent lesions and metastasis; hormones (e.g., progestin) to treat metastasis or precancerous lesions.
Radiation as adjunct to surgery and palliation; counseling for body image and sexual functioning alterations.