Alternative Names

Ovarian cancer is a disease produced by the rapid growth and division of cells within one or both ovaries—reproductive glands in which the ova, or eggs, and the female sex hormones are made. The ovaries contain cells that, under normal circumstances, reproduce to maintain tissue health. When growth control is lost and cells divide too much and too fast, a cellular mass or tumor is formed. If the tumor is confined to a few cell layers, for example, surface cells, and it does not invade surrounding tissues or organs, it is considered benign.


If the tumor spreads to surrounding tissues or organs, it is considered malignant, or cancerous. When cancerous cells break away from the original tumor, travel through the blood or lymphatic vessels, and grow within other parts of the body, the process is known as metastasis.

Many kinds of tumors can form in the ovaries. In fact, there are over 30 known histopathologic, or diseased tissue, types (see also Types of Ovarian Cancer). Experts group ovarian cancers within three major categories, according to the type of cells from which they were formed.

• Epithelial cancers, which are the most common ovarian cancers, arise from cells lining or covering the ovaries.
• Germ cell cancers start from germ cells (cells that are destined to form eggs) within the ovaries.
• Sex cord, stromal cell cancers, begin in the cells that hold the ovaries together and produce female hormones.