In a dramatic break from enshrined medical dogma, the US Preventive Task Force revised their guidelines for breast cancer screening with mammography, published in the Annals of Internal Medicine. While previous guidelines started at age 40, the panel now advises against screening the 40-50 age group, because current science based medicine indicates more harm than benefit. The guidelines are now up to date with the European Guidelines which screen women age 50-69 every two years.
Setting Back Evidence-Based-Medicine with Fear Mongering
The mainstream media, government and corporate medicine have strongly opposed the revised guidelines with slick marketing techniques, and fear mongering with appeals to emotion rather than evidence based medicine. Kathleen Sebelius, for example, appeared on national television advising women to ignore her own Department's task force panel, and start mammogram screening at 40. The opposing criticism has at times been bizarre and comical, with one author claiming the new guidelines will cause 47,000 deaths. This would be a impossible, since this exceeds the 30,000 deaths annually before the screening era. These opposing views avoid the real problems with screening mammography.
The Basic Problem With Screening Mammography
The basic problem with screening for breast cancer with mammography is the "reservoir of silent disease". A series of autopsy studies show that indolent breast cancers are common in the population. These early cancers, called DCIS, are silent and rarely cause clinical disease. The most impressive study was from Denmark in 1987. The Danish group used specimen radiography on autopsy samples, which most closely approximates what screening mammography does, searching for and finding small clusters of calcifications.The Danish team found breast cancer in one out of five women, most of which was DCIS (ductal carcinoma in situ).
One out of 5 women show breast cancer at autopsy, yet only 2 to 3 women per 10,000 die from breast cancer annually. (20% vs .03%) This indicates a disconnect between the huge reservoir of silent and clinically insignificant disease, and the much smaller number of invasive breast cancer presenting clinically.
DCIS in 18% of the Population
Current screening mammography technology detects 60,000 cases of DCIS annually, and yet, this is only a small fraction of total DCIS present in one out of five women in the population. DCIS is ductal carcinoma in situ, an early form of cancer with a good prognosis, a 98% five year survival with no treatment. I expect future refinements in xray technology to allow detection of even greater numbers of DCIS cases which have small calcifications. Ultimately the technology will catch up and replicate the Danish autopsy findings.
Do we really want to be detecting DCIS in one out of five women, and submit all these women to biopsy and lumpectomy? This is exactly what is advocated by the corporate-government-media sponsored mammography screening programs.
Just Stop Calling It Cancer
Recently, an NIH panel asked pathologists to stop calling DCIS cancer. Here is the NIH Consensus statement: "Because of the noninvasive nature of DCIS, coupled with its favorable prognosis, strong consideration should be given to elimination of the use of the anxiety-producing term "carcinoma" from the description of DCIS. "
Less is Better
I beg to offer a differing opinion more in line with the US Preventive Task Force revisions. The detection of massive numbers of cases of DCIS results in harm from over-treatment of the population with little benefit in terms of reduced mortality from breast cancer. This opinion is echoed by Dr Laura Essermanin a recent JAMA article on the limitations, and disappointing benefits of screening mammography.
Twenty Years of Data
We now have twenty years of breast cancer data during the screening era, and Dr Laura Esserman concludes, the incidence of early stage breast cancer has decreased due to mammography, yet the incidence rates for advanced cancers have not declined as expected. She says:
"One possible explanation is that screening may be increasing the burden of low-risk cancers without significantly reducing the burden of more aggressively growing cancers and therefore not resulting in the anticipated reduction in cancer mortality."