Ovarian cancer is an abnormal malignant growth located on the ovaries.
It is the fifth leading cause of cancer death in women, after lung cancer, breast cancer, colon cancer and pancreas cancer. It is also the leading cause of death from gynecologic malignancies and the second most commonly diagnosed gynecologic malignancy.
The exact cause of ovarian cancer is usually unknown. The disease is more common in industrialized nations, with the exception of Japan. In the United States, females have a 1.4% to 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 one quarter of ovarian cancer deaths occur in women between 35 and 54 years of age.
- Sense of pelvic heaviness
- Vaginal bleeding
- Weight gain or weight loss
- Abnormal menstrual cycles
- Unexplained back pain that worsens over time
- Increased abdominal girth
- Non-specific gastrointestinal symptoms:
- Vague lower abdominal discomfort
- 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/urgency
- Excessive hair growth
Note: There may be no symptoms until late in the disease.
In particular, women should watch for symptoms occurring in groups and lasting two weeks or more.
Women experiencing the above symptoms should request a blood test called CA-125, along with a complete pelvic examination.
Normal values range for CA-125 from 0 to 35. A high value in post-menopausal women may be an indication that the woman should receive further diagnostic screening or treatment. In pre-menopausal women, a value above 35 is not necessarily a cause for concern as values are often elevated due to a number of non-cancerous causes.
Further screening may involve CT scans, trans-vaginal ultrasounds, or retesting of the CA-125 value at a later date, to see if the value is normalising, or increasing.
Due to the non-specific common symptoms, it is difficult to diagnose ovarian cancer at its early stages (I and II), until it advances to later stages (III and IV).
Surgery is the preferred treatment and is frequently necessary for diagnosis. Studies have shown that surgery performed by a specialist in gynecologic oncology usually result in a higher rate of cure. Chemotherapy is used as after surgery to treat any residual disease. Radiation therapy is rarely used in ovarian cancer in the United States.
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. More than 60% of patients presenting with this disease already have stage III status.
Also, ovarian cancers shed malignant cells into the naturally occurring fluid within the abdominal cavity. These cells then have the potential to float in this fluid and frequently implant on other abdominal structures included the uterus, urinary bladder, bowel, and lining of the bowel wall. 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.
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 five-year survival rate for all stages is only 35% to 38%. If, however, diagnosis is made early in the disease, five-year survival rates can reach 90% to 98%. Germ Cell Ovarian Cancer has a much better prognosis, but is rarer.