The controversy over the recent mammogram screening recommendation from the United States Preventive Services Task Force (USPSTF) is quite interesting. The pieces of the recommendations that have generated the most controversy are as follows:
The USPSTF recommends against routine screening mammography in women aged 40 to 49 years. The decision to start regular, biennial screening mammography before the age of 50 years should be an individual one and take patient context into account, including the patient’s values regarding specific benefits and harms.
The USPSTF recommends biennial screening mammography for women aged 50 to 74 years.
Yesterday’s New York Times letters to the editor section and news section was typical of the unsophisticated coverage I’ve seen: a number of letters and quotes from women diagnosed in their 40s complaining that the new guidelines would have killed them, someone pointing out that cancer can grow a lot in two years, along with a couple people pointing out that a pile of anecdotes does not equal a well-conducted scientific study.
I’d like to see this discussion pushed to its logical conclusion. If the minimum screening age shouldn’t be increased to 50, why should it be left at 40? Why not lower it to 30? Or 20? Or even lower? And if two years is too long of an interval, are we sure one year is frequent enough? How about every 6 months? Or every 3 months? Or every day?
Surely it does make sense to have some guidelines. Mammography appears to have modest benefits, but there is also potential harm associated with screening. From the National Breast Cancer Coalition.
Myth #2: Mammograms can only help and not harm you.
False: What’ the risk? False positive results may lead to unnecessary, intrusive surgical interventions, while false negative results will not find cancerous tumors.
The American Cancer Society recommends annual screening mammograms, those performed without symptoms present, starting at age 40. But… it has been estimated that a woman’s cumulative risk for a false-positive result after ten mammograms is almost 50%; the risk of undergoing an unnecessary biopsy is almost 20%. In addition, women who are screened with mammography often have more aggressive and unneeded treatments. It is estimated that mammography screening has increased the number of mastectomies by 20% and the number of mastectomies and lumpectomies combined by 30%.
USPSTF does not take cost into account, although many have jumped to the conclusion that cost and “ObamaCare” are behind the recommendations. Personally I think it’s a good idea to take cost into account, although it should be done as a separate, transparent step after the clinical evidence is considered.
Although we don’t like to admit it, cost has to play a role somewhere along the way. If a mammogram is reimbursed ~$100 as it is now, cost may not be a big deal. But what if the cost were $1000, $10,000, $100,000, or $1,000,000? Should that not impact the guidelines?
I understand why people are worried about changes to guidelines, and I don’t totally disagree with their concerns. But diagnostic screening in general has risks as well as benefits. The aggregate benefits are often overstated by those who feel they’ve gained from screening –and especially by physicians, equipment makers, hospitals and labs that earn their living this way– while risks are not recognized or are suppressed.
Prostate screening is another good example of this phenomenon. See my coverage from a few years ago when the push began to lower the recommended age for PSA testing from 50 to 40.