Screening for cancer is examination (or testing) of people for early stages in the development of cancer even though they have no symptoms. Scientists have studied patterns of cancer in the population to learn which people are more likely to get certain types of cancer. They have also studied what things around us and what things we do in our lives may cause cancer. This information sometimes helps doctors recommend who should be screened for certain types of cancer, what types of screening tests people should have, and how often these tests should be done. Not all screening tests are helpful, and most have risks such as surgical complications from an abdominal operation performed because of an abnormal screening test for ovarian cancer. For this reason, scientists at the National Cancer Institute are studying many screening tests to find out how useful they are and to determine the relative benefits and harms.
If your doctor suggests certain cancer screening tests as part of your health care plan, this does not mean he or she thinks you have cancer. Screening tests are done when you have no symptoms. Since decisions about screening can be difficult, you may want to discuss them with your doctor and ask questions about the potential benefits and risks of screening tests and whether they have been proven to decrease the risk of dying from cancer.
If your doctor suspects that you have cancer, he or she will order certain tests to see whether you do. These are called diagnostic tests. Some tests are used for diagnostic purposes, but are not suitable for screening people who have no symptoms.
The purposes of this summary on ovarian cancer screening are to:
You can talk to your doctor or health care professional about cancer screening and whether it would be likely to help you.
The ovary is a female reproductive organ located in the pelvis. Its function is to produce female hormones and to store egg cells that, if fertilized by sperm, can develop into a baby. Women have two ovaries, one on each side of the uterus.
Ovarian cancer is the fifth leading cause of cancer death among women in the United States. The number of new ovarian cancer cases is decreasing slightly each year. In addition, fewer deaths are resulting from ovarian cancer.
Anything that increases a person’s chance of developing a disease is called a risk factor. Some of these risk factors for ovarian cancer are as follows:
Number of Children: Women who have never been pregnant are more likely to develop ovarian cancer than are women who have had children. In fact, the more times a woman has been pregnant, the less likely she is to develop ovarian cancer.
Oral Contraceptive Use: Women who use oral contraceptives (birth control pills) have a lower-than-average risk of developing ovarian cancer.
Breast Feeding: Women who breast feed their children have a lower-than-average risk of developing ovarian cancer.
History of Tubal Ligation or Hysterectomy: Women who have had a tubal ligation or hysterectomy, but have not had their ovaries removed, have a lower-than- average risk of developing ovarian cancer.
Family History of Ovarian Cancer: A woman whose mother, sister, or daughter has had ovarian cancer has a higher-than-average risk of developing ovarian cancer.
Fertility Drug Use: Women who use fertility drugs have a higher-than-average risk of developing ovarian cancer.
CA 125 Levels: Women with high levels of CA 125, a tumor marker that may indicate the presence of ovarian cancer cells, have a higher-than-average risk of developing ovarian cancer.
Another risk factor that has been suggested for ovarian cancer is the use of talcum powder. However, the evidence is conflicting and inconclusive.
Pelvic Examination: For this examination, the doctor feels the vagina, rectum, and lower abdomen for masses or growths. Generally, this type of examination discovers advanced disease.
Transvaginal Ultrasonography: During transvaginal ultrasonography, high-frequency sound waves are sent out by a probe inserted into the vagina. The waves bounce off the ovaries and produce echoes that are used to create a picture called a sonogram. Doctors examine the sonogram for echoes that might represent abnormal areas. Whether ultrasonography is effective in decreasing the number of deaths from ovarian cancer has not been determined in clinical trials.
CA 125: For this test, a blood sample is drawn and the amount of CA 125 present is measured in a laboratory. CA 125 is not always found in women with ovarian cancer; however, it may be present in women who have other types of cancer or noncancerous ovarian conditions. Studies suggest that CA 125 tests alone are not reliable for screening for ovarian cancer.
Pap Smear (or Test): This test is designed to screen for cervical cancer; however, occasionally it may find ovarian cancer. During a regular office visit, a doctor uses a wooden scraper and/or a small brush to collect a sample of cells from the cervix and upper vagina. These cells are placed on a slide and sent to a laboratory to check for abnormalities. It is possible that abnormal ovarian cells will be detected when the slide is examined for cervical cancer cells. This test is not reliable for the early detection of ovarian cancer.
Culdocentesis: During this procedure, a doctor inserts a needle through the vaginal wall and removes fluid from the space surrounding the ovaries. The fluid is then studied for the presence of abnormal cells. This procedure is not considered appropriate for routine screening.
Combination of Tests: Using multiple tests, such as pelvic examination, ultrasonography, and CA 125 measurement may be a way to improve the reliability of screening results. Scientists at the National Cancer Institute are studying the combination of ultrasonography and CA 125 measurement in reducing the number of deaths from ovarian cancer.
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Editorial changes were made to this summary.
For more information, U.S. residents may call the National Cancer Institute's (NCI's) Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237) Monday through Friday from 9:00 a.m. to 4:30 p.m. Deaf and hard-of-hearing callers with TTY equipment may call 1-800-332-8615. The call is free and a trained Cancer Information Specialist is available to answer your questions.
Web sites and Organizations
The NCI's Cancer.gov Web site provides online access to information on cancer, clinical trials, and other Web sites and organizations that offer support and resources for cancer patients and their families. There are also many other places where people can get materials and information about cancer treatment and services. Local hospitals may have information on local and regional agencies that offer information about finances, getting to and from treatment, receiving care at home, and dealing with problems associated with cancer treatment.
The NCI has booklets and other materials for patients, health professionals, and the public. These publications discuss types of cancer, methods of cancer treatment, coping with cancer, and clinical trials. Some publications provide information on tests for cancer, cancer causes and prevention, cancer statistics, and NCI research activities. NCI materials on these and other topics may be ordered online or printed directly from the NCI Publications Locator. These materials can also be ordered by telephone from the Cancer Information Service toll-free at 1-800-4-CANCER (1-800-422-6237), TTY at 1-800-332-8615.
The NCI's LiveHelp service, a program available on several of the Institute's Web sites, provides Internet users with the ability to chat online with an Information Specialist. The service is available from 9:00 a.m. to 10:00 p.m. Eastern time, Monday through Friday. Information Specialists can help Internet users find information on NCI Web sites and answer questions about cancer.
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PDQ is a comprehensive cancer database available on Cancer.gov.
PDQ is the National Cancer Institute's (NCI's) comprehensive cancer information database. Most of the information contained in PDQ is available online at Cancer.gov, the NCI's Web site. PDQ is provided as a service of the NCI. The NCI is part of the National Institutes of Health, the federal government's focal point for biomedical research.
PDQ contains cancer information summaries.
The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries are available in two versions. The health professional versions provide detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions provide current and accurate cancer information.
The PDQ cancer information summaries are developed by cancer experts and reviewed regularly.
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PDQ also contains information on clinical trials.
People who are at high risk for a certain type of cancer may want to take part in a clinical trial. A clinical trial is a study to answer a scientific question, such as whether a method of finding cancer earlier can help people to live longer. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients and those who are at risk for cancer. During screening clinical trials, information is collected about screening methods, the risks involved, and how well they do or do not work. If a clinical trial shows that a new method is better than one currently being used, the new method may become "standard."
Listings of clinical trials are included in PDQ and are available online at Cancer.gov. Descriptions of the trials are available in health professional and patient versions. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237); TTY at 1-800-332-8615.Physicians version: CDR0000062760