Types Of Ovarian Tumors

Women are born with two ovaries, one on either side of a woman's uterus. The ovaries are each about the size of an almond and produce the female hormones estrogen and progesterone as well as the ova (eggs). Ovarian tumors are growths of abnormal cells. These cells may be the noncancerous variety (benign) or cancerous (malignant). Benign tumors don't metastasize or spread to other parts of the body.

Cancerous ovarian tumors tend to spread to other tissue and organs in the pelvic and abdominal areas of the body. Sometimes they enter the bloodstream or lymph system and in this manner, find their way to other parts of the body.

Three Types

There are three main types of ovarian tumors. These are categorized according to their location in the ovary. The types of tumors include:

*Epithelial tumors—The majority of ovarian cancers, some 85-90%, form in the thin external tissue that sheaths the ovaries, the epithelium

*Germ cell tumors—These tumors are most often found in young women. They attack the cells in the ovary responsible for producing ova.

*Stromal tumors—These tumors are found in the tissue of the ovary where estrogen and progesterone are produced.  

Genetic Errors

Researchers still aren't sure of the exact cause of ovarian cancer. Some think the cancer stems from events following ovulation during a woman's childbearing years. Every month, an egg is released through a small tear in the ovarian follicle. As the body works to heal this miniscule tear, new cells form and divide at the site of the injury. There is a theory that during this time, genetic errors may occur. Another theory proposes that the increase of hormones prior to and during ovulation may trigger abnormal cell growth.

There are factors that increase a woman's risk for ovarian cancer. Having several risk factors means the risk is higher than average for this cancer, though by no means is cancer a foregone conclusion. One of the many risk factors for ovarian cancer is linked to certain inherited gene mutations.

The greatest risk factor for ovarian cancer is having breast cancer gene 1 or 2 (BRCA1 and BRCA2), even though most ovarian cancer patients don't have these mutations. At first these genes were thought specific to breast cancer, and so they were named. Women with BRCA1 mutation have a 35-70% increased risk for the cancer, while those with the BRCA2 mutation have a risk that is 10-30% higher. Most women carry a risk of only 1.5%. Ashkenazi Jewish women have the highest risk for this cancer.

Hereditary Syndrome

There's also a genetic syndrome that predisposes women to ovarian cancer. This is called hereditary nonpolyposis colorectal cancer (HNPCC). The females in a family with this inherited condition tend to get cancers of the uterine lining (endometrium), ovary, colon, and stomach. The risk of ovarian cancer with HNPCC is lower than that associated with the BRCA mutations.