Ovarian cancer

Alternative names:

cancer of the ovaries

Definition:

A malignant neoplasm (abnormal growth) located on the ovaries.

Causes, incidence, and risk factors:

The exact cause of ovarian cancer is unknown. Oddly enough, ovarian cancer is fairly uncommon, yet it is the 5th leading cause of cancer death in women. It is also the leading cause of death from gynecologic malignancies. This is a result of a number of factors. Malignant tumors of the ovaries develop quickly, often times involving both ovaries, and they shed malignant cells relatively early in the disease. These cells, which frequently land on the uterus, bladder, and bowel, can begin forming new tumor growths before cancer is ever even suspected. In addition to the rapid rate of development, there is not a screening test for ovarian cancer and symptoms of early disease are minimal, if even present. For these reasons, over 50 percent of women with ovarian cancer are in the advanced stages of the disease at the time of diagnosis.

Ovarian cancer is more common in industrialized nations, with the exception of Japan. In the United States, females have a 1.4 to 1.5% (1 out of 70 women) chance of developing ovarian cancer at some point in their lives. The incidence is higher in older women. More than half of the deaths from ovarian cancer occur in women between 55 and 74 years of age. Approximately one quarter of ovarian cancer deaths occur in women between 35 and 54 years of age.

Risk factors include poor reproductive history (infertility, repeated spontaneous abortions, delayed childbearing beyond age 30); past medical history of breast cancer (twice the risk of other women); family history of breast cancer or ovarian cancer in mother or sister; family history of Lynch syndrome II (the familial pedigree includes cancers of the colon, lung, prostate, and uterus), exposure to asbestos or high levels of radiation; high dietary fat; the use of talcum powder in the genital area; and the use of estrogen (other than that in oral contraceptives, which has actually been shown to have a protective effect).