The uterus is the female reproductive organ where the unborn baby grows and develops until birth. This muscular organ is connected to the vagina by the cervix and contains entrances for the two fallopian tubes, which transfer eggs from the ovaries. The uterus is a highly hormone sensitive organ with monthly bleeding and shedding cycles (menstruation) in the absence of pregnancy. The growth of the most common uterine cancer, adenocarcinoma, is also sensitive to female hormones. Uterine cancer usually arises from the lining of the uterus or endometrium. For most women, uterine cancer is brought to medical attention because of unanticipated or problematic bleeding from the uterus, usually occurring after menopause. Fortunately, approximately 80% of women diagnosed after developing abnormal bleeding will have cancer limited to the uterus (stage I and II) and a high proportion are cured.
Uterine (endometrial) cancer is one of the most common gynecologic cancers in women, with more than 42,000 new cases and more than 7,700 deaths from the disease each year. The incidence of uterine cancer would be even higher if it weren’t for the relatively large number of hysterectomies performed for non-cancerous reasons. Surgery is the primary treatment for uterine cancer and approximately 82% of women survive 5 years after diagnosis. For more information about the cause of uterine cancer and programs for early detection, go to Prevention and Screening.
In order to confirm the diagnosis of uterine cancer, a sample of tissue will need to be taken from the uterus and examined under a microscope. This sample may be obtained through a biopsy or through a procedure known as dilation and curettage (D&C).
There are several types of uterine cancer, which vary based on their appearance under the microscope. The most common type of uterine cancer is adenocarcinoma. Other variants of uterine cancer that behave more aggressively include serous carcinoma, uterine clear cell carcinoma and mixed type. These cancers, stage for stage, have a worse outcome than adenocarcinoma. Outcomes following treatment of adenocarcinoma can also be affected by the appearance of cancer when examined under the microscope. Doctors grade adenocarcinomas, as poorly, moderately or well differentiated. These terms describe how closely the cancer resembles normal cells of the uterus. In general, the less differentiated the cells, the more aggressive the cancer. More poorly differentiated cancers have a higher rate of recurrence. The reason doctors are interested in this is that more or better treatments may be indicated for patients with more aggressive cancers.
In addition to the type and grade of the cancer, the stage or extent of spread of cancer is the most useful predictor of survival and is relevant for treatment planning. Currently, surgery to remove the uterus, ovaries and lymph nodes is often relied upon to determine the stage of the cancer.
Other tests that may be utilized to help stage the cancer include magnetic resonance imaging (MRI) scans and ultrasound. The most common method for examining the uterus is with transvaginal sonography. During transvaginal sonography, an ultrasound apparatus is passed through the vagina in order to examine the uterus.
In order to learn more about the most recent information available concerning the treatment of uterine cancer, click on the appropriate stage.
Stage I: Cancer does not spread outside the body of the uterus.
Stage II: Cancer involves the body of the uterus and the cervix.
Stage III: Cancer extends outside the uterus, but is confined to the pelvis.
Stage IV: Cancer involves the bladder or bowel or distant sites.
Recurrent: Cancer has returned after initial treatment.
 American Cancer Society. Cancer Facts & Figures 2009. Available at: http://www.cancer.org/docroot/STT/STT_0.asp. Accessed September 14, 2009.