Transvaginal Ultrasound and CA 125 Blood Test Not Effective as Screening Test for Ovarian Cancer
Early detection and treatment can improve the prognosis of most cancers. Certain screening tests have been developed to help with early detection, such as
The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial was designed to examine the effectiveness of established and potential cancer screening tests. This portion of the study was focused on the use transvaginal ultrasound and a blood test called CA 125 to screen for ovarian cancer. The study, published in Obstetrics and Gynecology, found that the tests were more likely to create false positives than to find early ovarian cancer.
About the Study
The ovarian cancer portion of the study included 34,261 healthy women 55-74 years of age. The women all received four annual screenings. One half of the group received usual gynecological care. The other half of the group also had CA 125 and transvaginal ultrasounds done every year. Of the women that had the transvaginal and CA 125, 3,388 women (10%) had one or more positive screening tests. Of these women 1,170 (35%) had
Screening tests are not perfect and can give false positive and false negative results. A false positive means the test indicated a disease was present when there was in fact no disease. A positive predictive value (PPV) helps to determine how accurate the results are. In this case, over the four years of the study, the PPV for the transvaginal ultrasound and CA 125 was 1%-1.3%. This means that out of all the positive tests, cancer was actually present in only about 1% of the cases.
How Does This Affect You?
Doctors often use test results as a tool to help them reach a diagnosis, but the two tests examined here appear to be more stressful than successful. A false cancer diagnosis can cause a significant amount of distress for the person diagnosed and can lead to unnecessary, invasive procedures like biopsies. Screening for ovarian cancer has yet to come of age.
Although a reliable screening test for ovarian cancer remains unavailable, it is still worthwhile to see your primary care doctor and gynecologist on a regular basis. Screening tests for breast and
American Cancer Society
American College of Obstetricians and Gynecologists
Gynecologic Cancer Foundation
Buys SS, Patridge E, Greene MH, et al. Ovarian cancer screening in the Prostate, Lung, Colorectal and Ovarian (PLCO) cancer screening trial: findings from the initial screen of a randomized trial. Am J Obstet Gynecol. 2005 Dec;193(6):2183-4.
Partridge E, Kreimer AR, Greenlee RT, et al. Results from four rounds of ovarian cancer screening in a randomized trial. Obstet Gynecol. 2009 Apr;113(4):775-82.
Last reviewed June 2009 by
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © 2007 EBSCO Publishing All rights reserved.