TOO OFTEN, TOO LATE: Ovarian cancer cells, as seen by a scanning electron microscope. The image shows secretory cells with hairlike protrusions called microvilli (pink) as well as cilia (green) and mucus (yellow). Image: P. MOTTA AND S. MAKABE Photo Researchers, Inc.
Cancer screening is notoriously unreliable: a positive test often does not indicate disease, and a negative result does not always mean the patient can walk away with a handshake and a smile. In February many physicians and patients were encouraged by the results of a new test for ovarian cancer, hoping that it would be a noninvasive, cost-effective way to save thousands of lives. The findings offered proof of the enticing idea that within the thousands of proteins swimming in the blood lies a simple code that, if broken, will reveal whether cancer lurks in the body. But although the concept is promising, this technique is a long way from being useful within the general population.
News of this latest approach sparked widespread interest because none of today's diagnostic tests for ovarian cancer--including ultrasonography, pelvic exams and blood tests to detect levels of a protein called CA 125--can consistently detect the disease early, when the cure rate is around 90 percent. Instead most women are diagnosed once their cancer has progressed, when the chances of surviving five years drop to 35 percent.
This article was originally published with the title Lifting the Screen.