If you need further proof that medicine is just as much art as science, a new study shows that some common sense needs to prevail before rushing into possibly unnecessary prostate biopsies if there is a sudden spike in PSA levels. Several cancer organizations recommend biopsies if there is a quick change in what is known as PSA velocity. The new research calls that policy into question, concluding essentially that it has resulted in too many unnecessary biopsies for prostate cancer.
While PSA velocity has been statistically correlated with prostate cancer risk, until now nobody has really checked into how that correlation stacks up against other indicators. Andrew Vickers of Memorial Sloan-Kettering Cancer Center set out to answer that question by checking how well PSA velocity predicted cancer. It turned out that when other factors, including age, race and PSA levels were included, there was virtually no correlation between PSA velocity and prostate cancer.
The authors recommend that PSA velocity be stricken from biopsy guidelines. Also, in an accompanying editorial, Siu-Long Yao and Grace Lu-Yao, of the Cancer Institute of New Jersey, estimate that about 1 million men "may have been unnecessarily treated for clinically insignificant prostate cancer in the past 20 years.
"The shortcomings of PSA testing also remind us that there is still much art to the diagnosis and treatment of prostate cancer and that we, like the medieval physician Maimonides, must rely not only on our scientific skills but also on a combination of clear vision, kindness, and sympathy, as we see our patients through this often challenging disease," they conclude.
- read the release from Memorial Sloan-Kettering
- and the abstract from the Journal of the National Cancer Institute
- and check out the accompanying editorial