Screening for breast cancer in the oldest old

Geriatricians will frequently refer to "the old" and "the oldest old." Although what constitutes each category can sometimes be shifting, I think of the oldest old as those 85 years and above. I have also seen reference to "the very oldest old" (the oldest oldest old?) who are 100 years and up. In any case, what to do with people over 75 or so regarding cancer screening is controversial.

The general guidelines are to stop screening when life expectancy is not at least 10 years. That sounds good in theory, but as oncologists well know, prognostication for life expectancy is a tricky business. In addition, physicians tend to overestimate life expectancy, not underestimate, which means we are probably over screening women using mammograms. So, it is with a light heart that I came across this study in the Journal of Clinical Oncology. It was also written about in the New York Times recently. This is a SEER-Medicare (Surveillance, Epidemiology and End-Results-Medicare) analysis of women over 80 who had breast cancer. Those who had regular mammograms had better overall and breast–cancer-specific survival. The researchers tried to control for confounding by comorbid medical illnesses using the Charlson Comorbidity Index. Unfortunately, this is a crude way of controlling for only life threatening illness, and I believe more than just "serious" illnesses factor into whether or not to get a mammogram (functional ability comes to mind). Still, I think this study is a good step towards expanding the belief that there is some upper age limit beyond which we should never screen for cancer.