Cancer of the ovaries is the sixth most common cancer in women. About 7,000 new cases are diagnosed in the UK each year. It is a more frequent cause of death than the more common, but more easily detected, cancers of the uterus and cervix.
Women have two ovaries, located in the lower abdomen above and to either side of the uterus. About the size of apricots, the ovaries are connected to the uterus by fallopian tubes. Ovaries have two main functions. They produce oestrogen and progesterone, hormones which are responsible for the development of the features that distinguish women from men, their secondary sexual characteristics. The ovaries also regulate women’s periods and the development and release of an egg into the fallopian tube once a month during childbearing years.
Ovarian tumours can be either benign or malignant; it is not usually possible to tell them apart until they have been removed unless they have spread to other parts of the body. About 85% of ovarian tumours begin in the cells covering the outside of the ovaries, but they may also arise in the egg-producing cells (germ cells) or more rarely in the tissue that produces oestrogen and progesterone and holds each ovary together. While benign tumours do not spread, cancerous ovarian tumours will do so if left unchecked. They spread first into the tissues around the ovaries, then to the uterus, bladder, rectum, and the lining of the abdomen. Eventually, cancerous cells will reach the lymph nodes and spread throughout the body and invading and damaging other organs, such as the lungs.
The main risk factors for ovarian cancer are increasing age (ovarian cancers are rare before 45 and most occur between 65 and 74) and a family history of ovarian and/or breast cancer. However, less than 10% of ovarian cancer appears to have a family link. Slightly increased risks may be associated with not having children, taking fertility drugs, and with hormone replacement therapy. Slightly decreased risks are associated with having your tubes “tied” (tubal ligation), taking oral contraceptives, having children, and breast feeding.
It is difficult to detect ovarian cancer early – only about 25% of the cancers are found in the easily treatable stage, before they have spread beyond the ovaries. The symptoms of ovarian cancer are subtle and nonspecific. They include abdominal swelling and pain, indigestion, changes in passing urine and bowel habits, bloating and a feeling of pressure in the pelvis, weight changes, and unexplained vaginal bleeding. Since there are many non-cancerous conditions that can also cause these symptoms, it is important to consult your doctor if you are experiencing any symptoms.