Definition Ovarian cancer is a type of cancer that develops in a woman's ovary. It usually occurs in women older than 50 years. Any cell in the ovary can undergo a cancerous change. The most common form of ovarian cancer comes from the outer covering of the ovary, not the eggs. Treatment for this cancer can be very successful. The survival rate of women with ovarian cancer has improved over the last several years.
What is going on in the body? The ovaries are inside the woman's pelvic area. From puberty to menopause, the ovaries produce female hormones. These hormones regulate the menstrual cycle, or menstruation. The ovary also contains eggs. The hormones also regulate the release of eggs during the cycle. When an ovarian cell becomes cancerous, it will begin multiplying rapidly. A growth, or tumour, on the ovary forms as the cells multiply. This may interfere with the function of the ovary but not always. Cancer cells can break off from the tumour and directly spread into other areas inside the pelvis. Cancer cells can also enter the bloodstream. The cancer will then spread, or metastasise, to other areas of the body.
What are the signs and symptoms of the disease? There may be no symptoms in the early stage of the disease. The tumour must get quite large before it causes a problem. A tumour may be found early during a routine pelvic examination.
In the advanced stage, the tumour will eventually get so large that it presses on structures around the ovary. Because the rectum and bladder are nearby, the woman may have trouble urinating and become constipated. Sometime the tumour produces fluid that fills up the abdomen, a condition known as ascites. The fluid makes the abdomen swell and clothes feel tight. The woman may also experience bloating and indigestion from the pressure.
What are the causes and risks of the disease? There is no known cause of the disease. Women who have used oral contraceptives, or birth control pills, may be at lower risk than other women. The use of hormone replacement therapy at menopause has not been proven to increase risk. There is no proven link between diet and this cancer. A very small percentage of women (5%) with ovarian cancer have a close family history of it. Therefore, women with a family history may be at higher risk than other women. Women who have never had children are at higher risk.
What can be done to prevent the disease? There is nothing that can be done to prevent this cancer. Women with a very strong family history may have special tests done to detect it early. Removing the ovaries to prevent this cancer is controversial at this time. Other women should have a yearly pelvic examination.
How is the disease diagnosed? Finding a lump or mass during a pelvic examination does not mean that the woman has cancer. Special x-rays will be done to get a better idea of the type of mass it is. A small sample of blood will be drawn to test for a special substance that some ovarian cancers produce. This is called a tumour marker. Not every ovarian cancer makes it, and some normal cells make it. After those tests are done, a piece of the tumour must be removed to test for cancer.
Other surgery will be performed after the woman is found to have cancer. Other tests, such as CT scans of the abdomen and pelvis, will be done. The surgery and tests are to find out if the cancer has spread. This is important because the type of treatment depends on how far it has spread.
What are the long-term effects of the disease? Untreated ovarian cancer leads to death. Treatment can be effective, especially in the early stages.
What are the risks to others? There are no risks to others from this cancer.
What are the treatments for the disease? Surgery to remove the cancer and the surrounding tissues is an important part of treatment. This will get rid of most of the cancer. Any remaining cancer must be treated in another way.
Chemotherapy involves a combination of special medications given in the veins, which can be very effective in killing any remaining tumour. The medications travel in the bloodstream to places where the cancer may have spread. Some of the more common drugs are taxanes (Taxol) and platinum-based drugs (Cisplatin). Sometimes the chemotherapy is given directly into the abdomen through a special tube.
Radiation therapy has only limited use with this type of cancer. Usually it is directed at the abdomen because the cancer may have spread to several places there. Sometimes it is used along with chemotherapy.
What are the side effects of the treatments? The side effects of surgery include the following:
The woman will have the affected ovary removed. Sometimes both ovaries are removed. When both ovaries are removed, the woman will need replacement hormones to prevent the symptoms of menopause.
The uterus may also be removed. This will make the woman unable to bear children.
The side effects of chemotherapy depend on the specific medications used. Other side effects of chemotherapy include the following:
fatigue, caused by anaemia, a low number of red blood cells. This will clear up when the treatment ends.
increased risk of infection caused by the low number of white blood cells. This will also clear up when the treatment ends.
What happens after treatment for the disease? The woman will be followed closely to make the sure that the cancer is under control.
How is the disease monitored? Sometimes ovarian cancer produces a tumour marker called CA-125. If this was present at diagnosis, a small blood sample will be checked regularly to see if the level is changing. The level going up may indicate that additional treatment is needed. Specialised x-rays like CT scans of the abdomen and pelvis will also be done regularly. The results of these studies will also indicate how well the cancer responded to treatment.
Author: Miriam P. Rogers, EdD, RN, AOCN, CNS Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
