Doesn't distinguish aggressive tumors from slow-moving malignancies
MONDAY, May 3 (HealthDay News) -- A technique that urologists had hoped would make it possible to distinguish men with prostate cancer who need treatment from those who would only need watchful waiting didn't work well, researchers report.
The technique, called PSA kinetics, measures changes in the rate at which the prostate gland produces a protein called prostate-specific antigen. A significant increase in PSA kinetics, measured by the time during which PSA production doubles or increases at a rapid rate, is supposed to indicate the need for treatment, by radiation therapy or surgery.
PSA kinetics has long been used to measure the effectiveness of treatment. A number of cancer centers have started to use it as a possible method of distinguishing aggressive cancers that require treatment from those that are so slow-growing that they can safely be left alone.
Recent studies indicating that many men with slow-growing prostate cancers undergo unnecessary treatment have given urgency to the search for such a tool, especially considering that side effects of treatment can include incontinence and impotence.
But the study indicates that "PSA kinetics doesn't seem to be enough to show you who you should follow and who you should treat," said Dr. Ashley E. Ross, a urology resident at the Johns Hopkins University Brady Urological Institute, and lead author of a report on the technique published online May 3 in the Journal of Clinical Oncology.
The report describes the results of PSA kinetics measurements of 290 men with low-grade prostate cancer -- the kind that often doesn't require treatment -- for an average of 2.9 years. The results of PSA tests were compared with biopsies -- tissue samples -- that measured the progression of the cancers.
The trial is part of a study, under supervision of Dr. H. Ballentine Carter, d
All rights reserved