Ovarian cancer is a disease in which cancer cells grow in the ovaries. The ovaries are a pair of organs in the female pelvis that produce eggs and female hormones.

Cancer occurs when cells in the body (in this case ovarian cells) divide without control or order. Normally, cells divide in a regulated manner. If cells keep dividing uncontrollably when new cells are not needed, a mass of tissue called a tumor forms. The term cancer refers to malignant tumors, which can invade nearby tissues and can spread to other parts of the body. A benign tumor does not spread.

There are several cancers and several more benign tumors that may occur in the ovaries. Most cancers are called epithelial cell tumors, which are the focus of this article. These tumors may grow to a considerable size before they cause severe symptoms. Malignant ovarian tumors may spread by shedding cells into the peritoneal cavity, which then causes metastasis throughout the abdomen—making these tumors difficult to treat. Early detection is very important to help prevent the cancer from spreading.

Cancerous Mass in the Left Ovary

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Last reviewed December 2015 by Mohei Abouzied, MD  Last Updated: 12/20/2014