Ovarian epithelial cancer is a disease in which malignant (cancer) cells form in the tissue covering the ovary.
The ovaries are a pair of organs in the female reproductive system. They are in the pelvis, one on each side of the uterus (the hollow, pear-shaped organ where a fetus grows). Each ovary is about the size and shape of an almond. The ovaries make eggs and female hormones (chemicals that control the way certain cells or organs work).
Anatomy of the female reproductive system. The organs in the female reproductive system include the uterus, ovaries, fallopian tubes, cervix, and vagina. The uterus has a muscular outer layer called the myometrium and an inner lining called the endometrium.
Ovarian epithelial cancer is one type of cancer that affects the ovary. See the following PDQ treatment summaries for information about other types of ovarian tumors:
- Ovarian Germ Cell Tumors
- Ovarian Low Malignant Potential Tumors
- Unusual Cancers of Childhood
Women who have a family history of ovarian cancer are at an increased risk of ovarian cancer.
Anything that increases your risk of getting a disease is called a risk factor. Women who have one first-degree relative (mother, daughter, or sister) with ovarian cancer are at an increased risk of ovarian cancer. This risk is higher in women who have one first-degree relative and one second-degree relative (grandmother or aunt) with ovarian cancer. This risk is even higher in women who have two or more first-degree relatives with ovarian cancer.
Some ovarian cancers are caused by inherited gene mutations (changes).
The genes in cells carry the hereditary information that is received from a person's parents. Hereditary ovarian cancer makes up about 5% to 10% of all cases of ovarian cancer. Three hereditary patterns have been identified: ovarian cancer alone, ovarian and breast cancers, and ovarian and colon cancers.
There are tests that can detect mutated genes. These genetic tests are sometimes done for members of families with a high risk of cancer. See the following PDQ summaries for more information:
- Ovarian Cancer Screening
- Ovarian Cancer Prevention
- Genetics of Breast and Ovarian Cancer