Wednesday, July 24, 2013

Mammograms and Breast Cancer

     There has been much confusion and differing recommendations about how often women should get mammograms. Different groups and different countries have different recommendations, all of which are backed by "data". It is very confusing to read all the recommendations and then try to make a decision for oneself.

     The conflict arises, in part, from the difference between making recommendations for one million people and making a recommendation for one individual. If a mammogram shows breast cancer, then the payoff for the individual is 100% in that the breast cancer was detected.All  recommendations from different groups rest, in part, on prior assumptions, so that two groups can look at the same data and arrive at different conclusions.

     Right now the British recommend one mammogram every 3 years between the ages of 50 and 70. The American College of Radiology and the American Cancer society recommend annual mammograms from age 40.  Finally, the US Preventive Services Task Force recommends biannual screenings between the ages of 40 to 74, and the American College of Obstetricians and Gynecologists is not sure if screenings should be annual or biennial. And none of the groups has a  firm recommendation on the benefits of breast self-examination. I should also mention that to my knowledge, no one has compared the possible benefit of a screening mammogram every 6 months vs. once a year.

     The patient should make the decision, of course. With varying recommendations, one will generally pick the one that suits their needs the best. The only caveat is: if a mammogram shows cancer will you blame yourself for not having had one sooner?

     The bugbear is the damage caused by false positive mammograms and unnecessary biopsies. But the people making the recommendations do not, as a rule, discuss false positives with their patients. And the majority of patients would probably risk a negative biopsy in their search for a true one. It
 seems to me that once again we should yield to the patients' views, after outlining the recommendations of the different groups. And I do with that there had been a study comparing semi-annual memmograms with annual mammograms in high risk patients.