PSA Kinetics and Risk of Death From Prostate Cancer
Death from Prostate Cancer
In an accompanying editorial, Mitchell S. Anscher, M.D., of Duke University Medical Center, Durham, N.C., comments on the studies in this issue of JAMA on prostate cancer.
"As with most good retrospective studies, these 2 reports raise more questions than they answer. Given recent randomized trials reporting significant improvement in survival with chemotherapy for patients with hormone-refractory prostate cancer, a number of important questions persist: Is the definition of prostate cancer-specific mortality used in these studies still appropriate? In addition, which is the best index of change-in-PSA-with-time to use? Does it depend on the clinical situation; i.e., is PSA velocity more appropriate for newly diagnosed patients and PSADT more appropriate for patients recurring after primary therapy? What about patients who present with an abnormal result on their first-ever screening PSA measurement? Should the clinician wait 6 months and repeat the PSA measurement to calculate the PSA velocity? Also, should this information be used clinically at the present time, or are other nomograms [a chart or graphic representation of numerical relations that are connected by a line] better able to predict treatment outcome?"
"Good retrospective analyses serve to generate hypotheses for future clinical trials. The hypothesis that the rate of change in PSA with time predicts prostate cancer specific mortality must be validated prospectively. If proven to be correct, progress in prostate cancer research will proceed at a much faster pace, since conclusive answers to clinical questions will be available in 5 to 10 years, rather than once per generation," Dr. Anscher concludes.
(JAMA. 2005;294:493-494) - Chicago