Ovarian Cancer: Diagnosis and Staging
Causes and Complications
A specific cause of ovarian cancer has not been discovered, but certain risk factors are associated with the disease. For example, heredity is a major determinant; ovarian cancer cells often contain evidence of genetic damage. In some cases, there is a higher than normal risk of ovarian cancer and breast cancer in the same family, and this is usually related to a gene that is inherited. Most cases of ovarian cancer, however, are sporadic and are not associated with an inherited gene.
In a best-case scenario, your physician will detect ovarian cancer during your routine checkup. If not, it is likely that the disease will have spread dangerously before you are aware of it. Symptoms include frequent urination, constipation, abdominal swelling, and pain, which can be either gradual or sudden in onset. Urinary and bowel symptoms are caused by metastases (secondary growths) of the cancer directly on the affected organ. Pain can be due to pressure on nerves from the growing masses or from twisting of a tumor on the ovary, causing its blood supply to shut off. Abdominal swelling is due to the release of fluid by the tumor masses. The fluid, called ascites, fills the abdomen and can accumulate in large amounts. In some cases, this fluid can also spread to the lungs and cause shortness of breath.
It is possible to develop ovarian cancer without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing ovarian cancer. If you have a number of risk factors, ask your health care provider what you can do to reduce your risk.
Risk factors for ovarian cancer appear to be related mainly to your genetic makeup and the number of times you ovulate. Risk factors include:
Because only women have ovaries, ovarian cancer occurs exclusively in women.
Your risk of ovarian cancer increases if:
You have survived breast cancer
You have never been pregnant
Your ovaries do not function normally
You have had multiple miscarriages or abortions
You have taken ovulation-inducing (fertility) drugs such as clomiphene.
The risk of ovarian cancer tends to be slightly lower in women who:
Have taken birth control pills
Have had a tubal ligation
Have had a hysterectomy
In addition, each full-term pregnancy reduces your risk by about 10%. Breastfeeding appears to offer an additional reduction in risk.
Rates of ovarian cancer are three to five times higher in women with a mother or sister who had ovarian cancer. If two of your first-degree relatives have had ovarian cancer, your risk may be as high as 50%.
The incidence of ovarian cancer increases with age until the age of 75. It is rare before the age of 40.
The highest rates of ovarian cancer are in Scandinavian countries.
Some research suggests that the risk of ovarian cancer may increase with a higher dietary fat intake.