It's important to remember that simply measuring blood levels of CA-125 alone cannot effectively find early ovarian cancer. In many early-stage ovarian cancers, this molecule is not necessarily released in large amounts. False positives can also occur, as other conditions (endometriosis, the first trimester of pregnancy, or non-gynecological cancers) will elevate CA-125. In conjunction with a transvaginal ultrasound (TVU) screening, however, the CA-125 test can be very effective.
A transvaginal ultrasound, also known as an endovaginal ultrasound, involves the use of sound waves to delineate internal structures with a transducer placed in the vagina.
For this test, you lie on an examining table, on your back. A light sheet is provided to cover you during the procedure. A small handheld transducer that is covered with a latex condom is inserted into your vagina. The transducer produces images that can be seen on a video monitor, and a hard copy can be made on film. The test is completely painless and does not take much time.
Transvaginal ultrasound imaging is recommended for ovarian cancer screening in asymptomatic women at high risk for developing ovarian cancer. In a 1997 study of 14,469 women with no symptoms of ovarian cancer, researchers detected 17 ovarian cancers with TVU. Women who had abnormal findings on the first screening underwent additional tests to make sure the abnormality was not an ovarian cyst. Those who found that they did not have cysts then underwent a series of blood and ultrasound tests to determine whether there was a need for surgery. After surgery, researchers determined that 11 of the 17 cancers were Stage I (early stage). Although the total number of ovarian cancers detected was small, 65 percent of these tumors were detected at a stage when they are most likely to be curable.
