Rochester, Minnesota - Ovarian cancer is a type of cancer that begins in the ovaries. Women have two ovaries, one on each side of the uterus. The ovaries - each about the size of an almond - produce eggs (ova) as well as the hormones estrogen and progesterone.

Ovarian cancer often goes undetected until it has spread within the pelvis and abdomen. At this late stage, ovarian cancer is more difficult to treat and is frequently fatal. Early-stage ovarian cancer, in which the disease is confined to the ovary, is more likely to be treated successfully.

Surgery and chemotherapy are generally used to treat ovarian cancer.

Early-stage ovarian cancer rarely causes any symptoms. Advanced-stage ovarian cancer may cause few and nonspecific symptoms that are often mistaken for more common benign conditions, such as constipation or irritable bowel.

Signs and symptoms of ovarian cancer may include:

• Abdominal bloating or swelling
• Quickly feeling full when eating
• Weight loss
• Discomfort in the pelvis area
• Changes in bowel habits, such as constipation
• A frequent need to urinate

When to see a doctor

Make an appointment with your doctor if you have any signs or symptoms that worry you.

If you have a family history of ovarian cancer or breast cancer, talk to your doctor about your risk of ovarian cancer. Your doctor may refer you to a genetic counselor to discuss testing for certain gene mutations that increase your risk of breast and ovarian cancers. Only a small number of women are found to have genetic mutations that can lead to ovarian cancer.

It's not clear what causes ovarian cancer.

In general, cancer begins when a genetic mutation turns normal cells into abnormal cancer cells. Cancer cells quickly multiply, forming a mass (tumor). They can invade nearby tissues and break off from an initial tumor to spread elsewhere in the body (metastasize).

Types of ovarian cancer

The type of cell where the cancer begins determines the type of ovarian cancer you have. Ovarian cancer types include:

• Epithelial tumors, which begin in the thin layer of tissue that covers the outside of the ovaries. About 90 percent of ovarian cancers are epithelial tumors.
• Stromal tumors, which begin in the ovarian tissue that contains hormone-producing cells. These tumors are usually diagnosed at an earlier stage than other ovarian tumors. About 7 percent of ovarian tumors are stromal.
• Germ cell tumors, which begin in the egg-producing cells. These rare ovarian cancers tend to occur in younger women.