Fortunately, ovarian cancer is relatively rare. It has a lifetime risk of 1.3 percent. Ovarian cancer is unique to women. Unfortunately, ovarian cancer can be difficult to detect early and difficult to treat because it is often advanced stage disease when diagnosed. Only 45 percent of women with ovarian cancer survive five years. It is the fifth leading cause of cancer death in women behind lung, breast, colon, and pancreas.
The ovary is the female reproductive organ that produces eggs. The ovaries have about a million egg cells at birth and start to produce hormones and eggs that mature at puberty. When the ovaries start to function, normally one egg matures each month. Of the million eggs, only about 500 will successfully mature during a woman’s reproductive years.
Hormones from the brain stimulate the maturation of an egg that develops in a small cyst and then the egg is expelled from the cyst. This occurs on a regular cycle until the ovary runs out of eggs at about 55 years old. When the ovary stops functioning, a woman is referred to as entering menopause and the levels of hormones decrease and the eggs are no longer produced.
Ovarian function and egg maturation is inhibited by pregnancy, breast feeding and use of birth control medications. Under these conditions the ovary has the ability to become inactive or dormant under the influence of hormones. These factors can actually reduce ovarian cancer incidence.
There is no routine screening recommended for ovarian cancer for the average woman. PAP smears can be done to screen for cancer of the cervix but this does not screen for ovarian cancer. Studies to evaluate the usefulness of pelvic examinations, blood tests and ultrasound testing to screen for ovarian cancer have shown these strategies are not effective.
Signs and symptoms of ovarian cancer tend to be nonspecific. However, some symptoms might prompt testing: abnormal vaginal bleeding, pelvic or lower abdominal pain, unusual lower back pain, bloating of the abdomen, and a change in bowel or urinary habits. These symptoms can be due to a number of problems but ovarian cancer would be a consideration as a cause.
Some risk factors are associated with ovarian cancer. Certain genetic markers have an increased risk for both breast and ovarian cancer. These are referred to as BRCA mutations and are felt to be associated with 10-12 percent of ovarian cancers. Women who have blood relatives with breast and/or ovarian cancer may be candidates for genetic testing and closer monitoring. Some women who carry the BRCA mutation may elect to have their ovaries surgically removed. In addition, age is a factor since ovarian cancer is uncommon before age 55. Use of estrogen only supplements after menopause can increase risk. Also, obesity has been identified as a factor.
Factors associated with lower risk are long term use of birth control pills, birth control shots (depo provera), tubal ligation, removal of the ovaries, having had children, and history of breast feeding.
For the average woman, routine pelvic examinations have not been shown to effectively screen for ovarian cancer. Blood testing and ultrasound testing are not recommended for average risk patients. Some of these tests may be considered in women who are at high risk. Stay healthy my friends.
By: P. Michael Shattuck, M.D. – Community Health Network Family Physician