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What Is Ovarian Cancer?

Ovarian cancer is cancer that begins in your ovaries. Only women have ovaries, so only women get this kind of cancer.

Many types of tumors can start growing in the ovaries. Some are benign, meaning they are noncancerous. Benign tumors do not spread and can usually be�treated by removing one ovary, or part of the ovary. Ovarian cancer, however, is a malignant (cancerous) tumor. If a cancerous tumor is not treated, it can spread to other parts of the body.

To understand where the tumor is, it may help to know more about your ovaries.

Anatomy of the female pelvic area

A woman's reproductive system contains two ovaries. These are the other structures in that system:

  • Vulva

  • Vagina

  • Cervix

  • Uterus

  • Two fallopian tubes

Your ovaries are best known for hormone and egg production. They are located on either side of your pelvis. Each month, one of the ovaries releases an egg. After the egg leaves the ovary, it goes down the fallopian tube. If the egg connects with a sperm, it is fertilized and burrows into the wall of the uterus. There it grows to become a baby. If the egg is not fertilized, it leaves the body through the vagina along with the menstrual flow. The ovaries also make the hormones that control the development of certain parts of your body: breasts, body shape, and body hair. These hormones�also control your menstrual cycle.

The ovary is made up of many layers of cells. Cancer can affect any one or all of these layers. The doctor may take some cells during a biopsy to reveal what type of ovarian cancer you have. The type of cancer partly determines your options for treatment. These are the main types of ovarian cancer:

  • Epithelial ovarian cancer. This is the most common type of ovarian cancer. It arises on the surface of the ovary.

  • Primary peritoneal cancer. This rare cancer�type starts outside the ovaries in the tissue that lines the abdomen and pelvis. It is easily confused�with epithelial ovarian cancer.

  • Germ cell ovarian cancer. This cancer starts in the cells that form eggs in the ovary.

  • Stromal cell cancer. This cancer forms in the tissue that holds the ovaries in place.

  • Fallopian tube carcinoma. This rare cancer starts outside the ovary, but is treated as ovarian cancer.�