Wednesday, April 04, 2007

"The more things change"- "debate" on mammograms for age 40-49

Med Page Today gives a good summary of the some of the issues re-raised by recent recommendations of the American College of Physicians (ACP) regarding mammograms for women aged 40-49.

The ACP recommendations are contrary to those of the American Cancer Society, the American College of Obstetrics and Gynecology and even the USPSTF,an organization not known to be the first one to recommend anything.

The ACP committee seems to be saying rather than making a blanket recommendation for all women 40-49 to get annual or every other year mammogram that the woman should discuss the benefits and risks her physician. They suggest that the woman's individual risk be determined. They argue that the benefits-they seem to admit there are mortality benefits-are less than for older women and the risks ( mainly of false positives) are greater in the younger women and therefore a blanket recommendation is not appropriate.The ACP committee seems to have considerable faith in this individual risk assessment process even though there is no evidence that that approach is -in any way-superior to the blanket recommendation approach.

In my experience, in men with false positive PSA values and in women with suspicious findings on a mammogram that subsequently are demonstrated to be a false positive, the response almost always seems to be "thank goodness it wasn't cancer". Further, those folks almost always continue with their periodic screening.

I suspect that the ACP article will not change the practice of many primary care doctors for at least some of the following reasons:

The consensus of recommendation-making organizations is for routine screening.

Assessment of individual risk is very inexact and limited-most women with breast cancer do not have one of the traditional risk factors. Actually, I think it is worse than that and I have blogged about that issue before.

Discussions about risk is never easy and with the limited time physicians now have with each patient the logistics virtually prohibit a meaningful exchange,at least outside of a retainer practice.

The big elephant in the exam room is the issue of malpractice.Missed diagnosis of breast cancer is a major cause of malpractice suits. Who wants to be guilty of discouraging a mammogram ? "Doctor, were you not aware of the American Cancer Society's guidelines?"

It is interesting that everyone (ACP committee and all of the above mentioned groups) believe that for women fifty and over the data firmly indicate that the benefits of screening annually out weighs the risk. ACP and others have argued that the data for women 40-49 indicates a smaller mortality benefit and a greater risk so an individual risk assessment makes sense for the over 40 under 50 group. So a woman at fifty enters into a time when the doubt vanishes? The age grouping is arbitrary,statisticians could have as easily analyzed data in the age groups 44-53, 54-63 etc. There is no biological basis for believing that somehow things change at fifty. Risk assessment for a 54 year old woman without any of the generally recognized risk factors is just as imprecise and obscure as it is for a 46 year old woman. One has to weigh by some mysterious calculus the likelihood of cancer being detected by the test and cured by early treatment against the likelihood of having a false positive test leading to some measurable degree of anxiety and angst plus some unknown risk of detecting a type or subtype of breast cancer that didn't need to be treated anyway( if there is in fact such a thing). Try doing that in a 15 minute visit already filled with other important issues to discuss.

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