The American College of Physicians (ACP) has issued new clinical guidelines for screening mammography for women age 40 to 49.

The clinical guidelines and related articles appear in today’s edition of the Annals of Internal Medicine.

The ACP recommends that for every woman aged between 40 and 49 in their care clinicians should:

— Assess regularly her individual breast cancer risk and help her decide about screening mammography.
— Tell her about the potential harms and benefits of screening mammography.
— Base the screening mammography decision on potential harms and benefits, the woman’s preference and her breast cancer risk.

Senior Medical Associate in the Clinical Programs and Quality of Care Department of the ACP’s Medical Education and Publishing Division, and lead author of the guidelines, Dr Amir Qaseem said:

“It is important to tailor the decision of screening mammography by discussing the benefits and risks with a woman, addressing her concerns, and making it a joint decision between her and her physician”.

According to the ACP, breast cancer risk, and the potential harms and benefits of screening mammograpy are not evenly distributed among women between 40 and 49. This means the decision should be made by the patient and her doctor on a case by case basis.

On the plus side, screening mammography decreases breast cancer deaths, and if a woman has undetected breast cancer a mammogram will most likely find it earlier rather than later. But on the negative side, there is the chance that it will give a false positive result, lead to treatments that turn to be clinically unnecessary, and radiation exposure.

A careful assessment of a woman’s breast cancer risk is important, says the ACP. The 5-year breast cancer risk can vary from 0.4 per cent for a woman age 40 years with no risk factors to 6.0 per cent for a woman age 49 years with several risk factors.

The guidelines say the risk for invasive breast cancer can be estimated using the National Institutes of Health’s (NIH’s) calculator on their website, but cautions clinicians to be aware that while it takes into account many of the risk factors mentioned in the guidelines it has limitations.

The ACP says its guidelines have been rigorously developed and scrutinized based on the available empiricial research. They describe them as “evidence- based rather than expert-opinion or consensus guidelines”.

In revising the guidelines they re-evaluated the evidence on risks and benefits on mammography screening for women age 40 to 49; they reviewed studies from the original mammography trials and another 117 studies.

The ACP also recommends more research be done to assess the benefits and harms of the different types of breast cancer screening for women between 40 and 49.

In the US, breast cancer is the most common cancer in women, after skin cancer; and it is the second biggest cancer killer in women, after lung cancer.

According to the American Cancer Society, this year approximately 178,000 women will discover they have breast cancer, and 40,000 women will die from it.

“Screening Mammography for Women 40 to 49 Years of Age: A Clinical Practice Guideline from the American College of Physicians.”
Amir Qaseem, Vincenza Snow, Katherine Sherif, Mark Aronson, Kevin B. Weiss, Douglas K. Owens, for the Clinical Efficacy Assessment Subcommittee of the American College of Physicians.
Annals of Internal Medicine 3 April 2007, Volume 146 Issue 7, Pages 511-515

Click here for full text of the Guidelines.

Click here for NIH breast cancer risk calculator.

Written by: Catharine Paddock
Writer: Medical News Today