CHICAGO (Reuters) - Cancer experts fear new U.S. breast imaging guidelines that recommend against routine screening mammograms for women in their 40s may have their roots in the current drive in Washington to reform healthcare. Critics of the guidelines, issued on Monday by the U.S. Services Task Force, an independent panel sponsored by the U.S. Agency for Healthcare Quality, say the new guidelines are a step backward and will lead to more cancer deaths. Here are some of their concerns. * Dr Carol Lee, chairwoman of the American College of Radiology Breast Imaging Commission, said she fears insurers -- both...