The American Cancer Society's (ACS) newly released guidelines for the early detection of breast cancer further confuse an already confusing and differing array of early breast cancer detection recommendations.

The new ACS guidelines recommend that women 40 to 44 should have the choice to start yearly mammography if they wish to do so. The guidelines recommend annual mammography on women 45 to 54; women 55 and older should switch to mammograms every two years or continue with yearly mammography. And they recommend that women continue to have screening mammography as long as they are healthy and expected to live 10 years or longer.

The older ACS guidelines, still endorsed by the American College of Radiology and the Society of Breast Imaging, were simpler: yearly mammographic screening beginning at age 40.

Widespread mammographic screening in the U.S. started in the 1980s after multiple studies in various countries documented that early detection of breast cancer with mammographic screening saves lives. The screening never reached a level of more than 60 percent of eligible women in our country and recently has somewhat declined, coinciding with the recommendation issued by the U.S. Preventive Services Task Force in 2009 that only women 50 to 74 should be screened every two years.

Yet there is one fact that all of the above groups agree upon: Yearly screening beginning at age 40 saves the most lives, compared with the new ACS guidelines, and certainly the task force guidelines.

The task force, in particular, does not agree that saving those additional lives with screening is worth the costs — namely, the anxiety experienced when the approximately 10 percent of women are called back for additional views after a screening exam, and the cost of the biopsies performed in approximately 1.5 percent of women screened, especially those that turn out to be ultimately unnecessary because they are benign. Of course, the fact that they are benign is known only after the biopsy.

An interesting sidebar to this controversy is the Are You Dense Advocacy, which has successfully encouraged legislation in 24 states and counting, including Minnesota, that calls for more screening, not less. This effort advocates that women with dense breast tissue should be informed that mammography is less accurate in such tissue and that they are at somewhat greater risk for getting breast cancer — the point being that they should consider more early breast cancer screening with another test such as a vascular-based study (MRI, contrast mammography, radionuclide breast imaging) or ultrasound. This would be in addition to screening with mammography, which while not working as well in women with dense breast tissue, still works.

As it turns out, mammography has made vast improvements in women with dense breast tissue with the widespread use of digital mammography, and now with the newly introduced tomosynthesis, which is also called "3-D" mammography, the latter only now starting to be covered by insurers.

And so where does that leave us? After all, screening for the early detection of breast cancer is not mandatory. It's a choice — if you are insured or have the money to pay for it.

If women choose to be screened and they want to decrease their chance of dying from breast cancer the most, then they should get yearly mammography beginning at age 40 with digital and perhaps "3-D" mammographic equipment. If they are informed that they have dense breast tissue, or better yet, if a detailed enough history is taken to determine whether they may be at increased risk for a variety of reasons, then additional screening strategies may be considered, such as MRI. And there are certain high-risk patients who should begin screening before age 40, such as those with a genetic mutation or those having a history of mantle irradiation for Hodgkin's disease.

On the other hand, following the somewhat-lesser ACS guidelines or the even-less-stringent Preventive Services Task Force guidelines is certainly better than nothing. Even those lesser guidelines, if followed by the vast majority of eligible women, would substantially decrease the risk of dying from breast cancer, which is after all, a terrible disease.

Dr. Tim H. Emory is director of breast imaging at the University of Minnesota Breast Center.