Ovarian cancer is cancer that starts in the ovaries. The ovaries are the female reproductive organs that produce eggs.
Cancer - ovaries
Causes, incidence, and risk factors:
Ovarian cancer is the fifth most common cancer among women, and it causes more deaths than any other type of female reproductive cancer.
The cause is unknown.
The risk for developing ovarian cancer appears to be affected by several factors. The more children a woman has and the earlier in life she gives birth, the lower her risk for ovarian cancer. Certain genes (BRCA1 and BRCA2) are responsible for a small number of ovarian cancer cases. Women with a personal history of breast cancer or a family history of breast or ovarian cancer have an increased risk for ovarian cancer.
Older women are at highest risk. About two-thirds of the deaths from ovarian cancer occur in women age 55 and older. About 25% of ovarian cancer deaths occur in women ages 35 - 54.
Hormone therapies and ovarian cancer:
- Women who take estrogen replacement only (not with progesterone) for 5 years or more seem to have a higher risk of ovarian cancer.
- Birth control pills decrease the risk of ovarian cancer.
- More recent studies suggest that fertility drugs do not increase the risk for ovarian cancer.
Ovarian cancer symptoms are often vague. Women and their doctors often blame the symptoms on other, more common conditions. By the time the cancer is diagnosed, the tumor has often spread beyond the ovaries.
Early-stage ovarian cancer can cause symptoms, although these symptoms also occur with many other conditions. You should see your doctor if you have the following symptoms on a daily basis for more than a few weeks:
Other symptoms are also seen with ovarian cancer. However, these symptoms are also common in women who do not have cancer:
- Abnormal menstrual cycles
- Digestive symptoms:
- Sense of pelvic heaviness
- Swollen abdomen or belly
- Unexplained back pain that worsens over time
- Vague lower abdominal discomfort
Weight gain or loss
Other symptoms that can occur with this disease:
Signs and tests:
A physical examination may reveal a swollen abdomen and fluid in the abdominal cavity (ascites ). A pelvic examination may reveal an ovarian or abdominal mass .
Lab tests that may be done include:
Imaging tests that may be done include:
Pelvic laparoscopy or exploratory laparotomy may be done to evaluate symptoms and get a biopsy to help make the diagnosis.
No lab or imaging test has ever been shown to be able to diagnose ovarian cancer in its early stages (screening).
Surgery is part of the treatment for all stages of ovarian cancer. For earlier stages, it may be the only treatment. Surgery involves:
- Removal of the uterus (total hysterectomy )
- Removal of both ovaries and fallopian tubes (bilateral salpingo-oophorectomy)
- Partial or complete removal of the omentum, the fatty layer that covers and pads organs in the abdomen
- Examination, biopsy, or removal of the lymph nodes and other tissues in the pelvis and abdomen
Studies have shown that surgery performed by a specialist in gynecologic oncology results in a higher success rate.
Chemotherapy is used after surgery to treat any remaining disease. Chemotherapy can also be used if the cancer comes back. Chemotherapy may be given into the veins, or sometimes directly into the abdominal cavity (intraperitoneal).
Radiation therapy is rarely used in ovarian cancer in the United States.
After surgery and chemotherapy, patients should have:
- A physical exam (including pelvic exam) every 2 - 4 months for the first 2 years, followed by every 6 months for 3 years, and then annually
- A CA-125 blood test at each visit if the level was initially high
- Your doctor may also order a computed tomography (CT ) scan of your chest, abdomen, and pelvic area and a chest x-ray.
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.
- About 76% of women with ovarian cancer survive 1 year after diagnosis.
- About 45% live longer than 5 years after diagnosis.
- If diagnosis is made early in the disease and treatment is received before the cancer spreads outside the ovary, the 5-year survival rate is about 94%.
- Spread of the cancer to other organs
- Loss of organ function
- Fluid in the abdomen (ascites )
- 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 pelvic examination. Routine pelvic examinations are recommended for all women over 20 years old.
Call for an appointment with your provider if you have symptoms of ovarian cancer.
Having regular pelvic examinations may decrease the overall risk. Screening tests for ovarian cancer remains a very active research area. To date, there is no cost-effective screening test for ovarian cancer. More than 50% of women with ovarian cancer are diagnosed in the late stages of the disease.
Recent research has shown that preventive surgery to remove the ovaries in women who have a mutation in the BRCA1 and BRCA2 genes can dramatically reduce their risk of developing ovarian cancer.
Mørch LS, Løkkegaard E, Andreasen AH, Krüger-Kjaer S, Lidegaard O. Hormone therapy and ovarian cancer. JAMA. 2009;302:298-305.
National Comprehensive Cancer Network. National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology: Ovarian Cancer. 2009;v.2.
Jensen A, Sharif H, Frederiksen K, Kjaer SK. Use of fertility drugs and risk of ovarian cancer: Danish population based cohort study. BMJ. 2009;338:b249.