Carcinoma of the Endometrium
Introduction
Essentials of Diagnosis
- Abnormal bleeding is the presenting sign in 80% of cases.
- Pap smear frequently negative.
- After a negative pregnancy test, endometrial tissue is required to confirm the diagnosis.
General Considerations
Adenocarcinoma of the uterine corpus is the second most common cancer of the female genital tract. It occurs most often in women 50-70 years of age. Some patients will have taken unopposed estrogen in the past; their increased risk appears to persist for 10 or more years after stopping the drug. Obesity, nulliparity, diabetes, and polycystic ovaries with prolonged anovulation and the extended use of tamoxifen for the treatment of breast cancer are also risk factors.
Abnormal bleeding is the presenting sign in 80% of cases. Endometrial carcinoma may cause obstruction of the cervix with collection of pus (pyometra) or blood (hematometra) causing lower abdominal pain. However, pain generally occurs late in the disease, with metastases or infection.
Papanicolaou smears of the cervix occasionally show atypical endometrial cells but are an insensitive diagnostic tool. Endocervical and endometrial sampling is the only reliable means of diagnosis. Adequate specimens of each can usually be obtained during an office procedure performed following local anesthesia (paracervical block). Simultaneous hysteroscopy can be a valuable addition in order to localize polyps or other lesions within the uterine cavity. Vaginal ultrasonography may be used to determine the thickness of the endometrium as an indication of hypertrophy and possible neoplastic change.
Pathologic assessment is important in differentiating hyperplasias, which often can be treated with cyclic oral progestins.
Prevention
Prompt endometrial sampling for patients who report abnormal menstrual bleeding or postmenopausal uterine bleeding will reveal many incipient as well as clinical cases of endometrial cancer. In comparison with the use of unopposed estrogen for menopausal therapy, there is a relative risk of endometrial cancer of 0.3 among women using continuous combined regimens of estrogen and progestin. Younger women with chronic anovulation are at risk for endometrial hyperplasia and subsequent endometrial cancer. They can reduce the risk of hyperplasia almost completely with the use of oral contraceptives or cyclic progestin therapy.
Staging
Examination under anesthesia, endometrial and endocervical sampling, chest x-ray, intravenous urography, cystoscopy, sigmoidoscopy, transvaginal sonography, and MRI will help determine the extent of the disease and its appropriate treatment. The staging is based on the surgical and pathologic evaluation.
Treatment
Treatment consists of total hysterectomy and bilateral salpingo-oophorectomy. Peritoneal material for cytologic examination is routinely taken. Preliminary external irradiation or intracavitary radium therapy is indicated if the cancer is poorly differentiated or if the uterus is definitely enlarged in the absence of myomas. If invasion deep into the myometrium has occurred or if sampled preaortic lymph nodes are positive for tumor, postoperative irradiation is indicated.
Palliation of advanced or metastatic endometrial adenocarcinoma may be accomplished with large doses of progestins, eg, medroxyprogesterone, 400 mg intramuscularly weekly, or megestrol acetate, 80-160 mg daily orally.
Prognosis
With early diagnosis and treatment, the overall 5-year survival is 80-85%. With stage I disease, the depth of myometrial invasion is the strongest predictor of survival, with a 98% 5-year survival with < 66% depth of invasion and 78% survival with = 66% invasion.
Preferences:
Hernandez E: Endometrial carcinoma: a primer for the generalist. Obstet Gynecol Clin North Am 2001;28:743.
Mariani A et al: Surgical stage I endometrial cancer: predictors of distant failure and death. Gynecol Oncol 2002;87:274.
Revision date: June 18, 2011
Last revised: by Tatiana Kuznetsova, D.M.D.