Rethinking the screening mammogram

This study analyzed data from women over 40 and compared the size of breast cancers at the time of diagnosis detected in the 1970s (before mammography became common) with the size of tumors detected between 2000 and 2002, when screening mammography was routine. Treatments and rates of death due to breast cancer 10 years after the diagnosis were also analyzed. The study found that: As more women underwent routine screening mammograms, more small breast cancers were detected. Many of these tumors were restricted to the ducts within the breast (called ductal carcinoma in situ), and even without treatment would never threaten the health of the woman. The detection of larger, more aggressive breast cancers was unchanged in frequency between the pre-mammogram and more recent time periods. This is important since, if screening mammograms caught these cancers earlier, in theory, the frequency of detecting these more dangerous tumors should be falling. Are there benefits of a screening mammogram? The study’s authors did not suggest that mammography is useless. They estimated that about 20% of women with small tumors that could only be detected with a mammogram received therapy that might be lifesaving. But the other 80% of women did not benefit. Similarly, estimates suggest that about two-thirds of the reduction in breast cancer deaths in recent years is due to better treatments, not better detection. Some additional reduction may be related to falling rates of post-menopausal hor...
Source: Harvard Health Blog - Category: Consumer Health News Authors: Tags: Health Source Type: blogs