January 12, 2011
THE DELUSION OF PERFECTION:
Cancer breakthrough -- or nightmare?: New cancer detection test may have downside (Dr. H. Gilbert Welch, 1/11/11, WPRI)
A simple blood test. It's able to detect minute quantities of cancer cells that might be circulating in your bloodstream.It's reported to be able to detect a single cell. It's intended to allow cancer patients to start treatment much earlier.
It's supposed to save lives. It's a cancer breakthrough.
But it's not that simple. The test could just as easily start a cancer epidemic.
We've seen it before. Twenty years ago another simple blood test was introduced. Twenty years later over 1 million Americans had been treated for a cancer that was never going to bother them.
The test was the PSA. It is able to detect minute quantities of prostate specific antigen -- minute as in one-billionth of gram. Turned out a lot of men had "abnormal" PSAs. Many were found to have microscopic cancers, far more than would ever suffer from prostate cancer.
"[H]e was confident in his science, and felt that he could draw a magic circle round her within which no evil might intrude."
