Cancer - ovaries
Ovarian cancer is a malignant neoplasm (abnormal growth) located on the ovaries.
Causes, incidence, and risk factors
Ovarian cancer is fairly uncommon, yet it is the 5th leading cause of cancer death in women and the leading cause of death from gynecologic malignancies. The cause is unknown. The disease is more common in industrialized nations, with the exception of Japan. In the United States, females have a 1.4 - 2.5% (1 out of 40-60 women) lifelong chance of developing ovarian cancer.
Older women are at highest risk. More than half of the deaths from ovarian cancer occur in women between 55 and 74 years of age and approximately 25% of ovarian cancer deaths occur in women between 35 and 54 years of age.
Ovarian cancer is disproportionately deadly for a number of reasons. First, symptoms are vague and non-specific, so women and their physicians frequently attribute them to more common conditions. By the time the cancer is diagnosed, the tumor has often spread beyond the ovaries.
Also, ovarian cancers shed malignant cells that frequently implant on the uterus, bladder, bowel, and lining of the bowel wall (omentum). These cells can begin forming new tumor growths before cancer is even suspected.
Second, because no cost-effective screening test for ovarian cancer exists, more than 50% of women with ovarian cancer are diagnosed in the advanced stages of the disease.
The risk for developing ovarian cancer appears to be affected by several factors. The more children a woman has, the lower her risk of ovarian cancer. Early age at first pregnancy and the use of some oral contraceptive pills have also been shown to have a protective effect. In contrast, the use of fertility drugs may be associated with an increased chance of developing this cancer, although there is ongoing controversy over this.
Certain genes may also increase risk, including BRCA1 and BRCA2, which also increase Breast cancer risk and the chances that a woman will be affected by either cancer at a younger age. Patients with a personal history of Breast cancer, or a family history of breast or ovarian cancer, may have an elevated risk. A strong family history of uterine, colon, or other gastrointestinal cancers may indicate the presence of a syndrome known as hereditary non-polyposis colon cancer (HNPCC), which confers a higher risk for developing ovarian cancer.
Other factors that have been investigated, such as talc use, asbestos exposure, high dietary fat content, and childhood mumps infection, are controversial and have not been definitively proven.
- Sense of pelvic heaviness
- Vague lower abdominal discomfort
- Vaginal bleeding
- Weight gain or loss
- Abnormal menstrual cycles
- Unexplained back pain that worsens over time
- Increased abdominal girth
- Non-specific gastrointestinal symptoms:
- Increased gas
- Lack of appetite
- nausea and vomiting
- Inability to ingest usual volumes of food
Additional symptoms that may be associated with this disease:
- Increased urinary frequency or urgency
- Excessive hair growth
There may be no symptoms until late in the disease.
Signs and tests
Physical examination may reveal increased abdominal girth and ascites (fluid within the abdominal cavity). Pelvic examination may reveal an ovarian or abdominal mass.
- Blood chemistry
- Quantitative serum HCG (blood pregnancy test)
- Alpha fetoprotein
- GI series
- Exploratory laparotomy
- An abdominal CT scan or MRI of abdomen
Surgery is the preferred treatment and is frequently necessary for diagnosis. Studies have shown that surgery performed by a specialist in gynecologic oncology results in a higher rate of cure. Chemotherapy is used as after surgery to treat any residual disease. Chemotherapy can also be used to treat women who have a recurrence. Radiation therapy is rarely used in ovarian cancer in the United States.
The stress of illness may be eased by joining a support group whose members share common experiences and problems. See cancer - support group.
Ovarian cancer is rarely diagnosed in its early stages. It is usually quite advanced by the time diagnosis is made. The outcome is often poor. The 5-year survival rate for all stages is only 35% to 38%. If, however, diagnosis is made early in the disease, 5-year survival rates can reach 90% to 98%.
- Metastasis spread of the cancer to other organs
- Progressive function loss of various organs
- Ascites (fluid in the abdomen)
- Blockage of the intestines
Calling your health care provider
Call for an appointment with your health care provider if you are a woman over 40 years old who has not recently had a Pap smear and pelvic examination (routine Pap smears and pelvic examinations are recommended for all women over 20 years old).
Call for an appointment with your provider if symptoms appear which may be associated with this disease.
Having regular pelvic examinations may decrease the overall risk. However, no definitive prevention strategy is known. Screening tests for ovarian cancer remains a very active research area.
Studies have shown that there may be a lower risk of ovarian cancer in patients who have used the oral contraceptive pill, although certain types are of more benefit than others. Recent research has shown that for women with mutation in BRCA1 and BRCA2 (the genes that are related to the breast-ovarian cancer syndrome), surgery to remove the ovaries can dramatically reduce the risk of developing ovarian cancer.
Last Edited: 11 Aug. 2005
by Arthur A. Poghosian, M.D.