Editor's note: CNN conditions expert Dr. Otis Webb Brawley is the chief medical officer of the American Cancer Society, a world-renowned cancer expert and a practicing oncologist. He is also the author of the book, "How We Do Harm: A Doctor Breaks Ranks About Being Sick in America."
(CNN) -- Q: This week the U.S. Preventive Services Task Force issued preliminary guidelines for ovarian cancer screening. It recommends against routine screening saying that the risk of false positive diagnoses outweighs the benefits. How can this be and why is it so hard to find a good screening test for ovarian cancer?
A: The U,S. Preventive Services Task Force is a group of medical experts who assess the scientific literature on an issue, such as ovarian cancer screening, before making a recommendation. They do influence how doctors practice medicine.
The statement recommends against routine ovarian cancer screening because they find the evidence of harm associated with screening is greater than the evidence of benefit.