Cancer of the ovary is a disease that affects one or both ovaries, the two organs on either side of the uterus. Ovaries contain eggs that are released when a woman ovulates. They also produce hormones for reproduction. If cancer of the ovary is found and treated early, the cure rate is good. Patients whose cancer has not spread outside the ovary have a 90–
95% chance of living five years or longer after treatment.

What is Cancer?

Normal, healthy cells throughout a person's body grow, divide, and are replaced on a routine basis. Sometimes, cells develop abnormally and begin to grow out of control. When this happens, the cells form growths or tumors. Tumors can be benign (not cancer) or malignant (cancer). Benign tumors do not spread, or metastasize, to other body tissues. Malignant tumors can invade and destroy nearby healthy tissues and organs. Cancer cells also can spread to other parts of the body and form new cancerous areas. There are three types of ovarian cancer:

• Epithelial
• Germ cell tumors
• Sex cord-stromal tumors

The type of cancer is based on the type of cells in which it occurs. Epithelial cancers are most common. About 85–90% of all ovarian cancers arise from epithelial cells. These are the cells that cover the surface of the ovaries. Most women who get this type of ovarian cancer are older than 40 years. About 5% of ovarian cancers are germ cell tumors. Germ cells are the cells in the ovary that develop into eggs. Sex cord-stromal tumors occur in connective tissue inside the ovary.

Who Is at Risk?

About 3% of all new cancers found in women each year are ovarian cancers. Women of any age can have cancer of the ovary, but the risk increases with age. The most common type occurs most often in women between the ages of 50 and 75. Half of all ovarian cancers are found in women older than 63. Cancer of the ovary is much less common in women younger than 40. It occurs more often in white women than in women of other races.

 Learn more about ovarian cancer.