Analysis of data from > 200,000 men, all enrolled in a large California managed care health plan, appears to offer us some “insight into the usefulness of PSA velocity as a detection marker for aggressive prostate cancer.”
Wallner et al. set out to see whether the rate of change of total PSA levels could be used as an accurate means to detect prostate cancer and (perhaps more importantly) to assess whether that rate of change of PSA level was a better measure of risk for prostate cancer among patients being seen in community-based, general practice settings. Additional information about the study is provided in a media release issued by Kaiser Permanente.
The authors carried out a retrospective analysis of data from 219,388 community-dwelling men, all aged ≥ 45 years, and all enrolled in the Kaiser Permanente Southern California health plan. These patients had no history of prostate cancer and at least three PSA measurements. They were all followed, from 1 January 1998 to 31 December 2007, for the development of biopsy-confirmed prostate cancer. The accuracy of prostate cancer prediction was evaluated using mathematical models for all prostate cancer and for aggressive forms of prostate cancer (i.e., a Gleason score ≥ 7) using the patients’ PSA velocity data and compared to predictions based on a single measure of PSA level.
Here is what Wallner and her colleagues report:
- The 219,388 men in this cohort had an average (mean) change in their PSA levels of 2.9 percent per year.
- The rate of this change in PSA levels increased modestly with age (P ≤ 0.001).
- Annual percentage changes in PSA levels were able to accurately predict
- The presence of any prostate cancer
- The presence of aggressive disease
- Annual percentage changes in PSA levels had greater predictive accuracy for aggressive disease than did a single measurement of PSA alone.
The data from this study are in direct contrast with the data from studies by Vickers, Lilja, and others that have shown that PSA velocity is no better than a single PSA assay in the prediction of risk from prostate cancer, so it does present us with a very real problem. On the other hand, there are other studies that have suggested that PSA velocity may be used to improve the detection of prostate cancer and/or aggressive disease.
We are currently attempting to obtain a copy of the full text of this article from the authors. If we are able to obtain a full text of the paper, we may be in a better position to understand how the data from this paper may help us to understand the degree to which PSA velocity is clinically meaningful in determining risk for prostate cancer (and most particularly for more aggressive forms of this disease).
Filed under: Diagnosis, Risk | Tagged: Diagnosis, PSA, risk, velocity |
THE "NEW" PROSTATE CANCER INFOLINK 
Kaiser finally using its enormous database for prostate cancer data. They have been disappointingly slow to use the power of their system to help with the screening conundrum in prostate cancer. They do not even have a uniform treatment approach across their regions.
(I am a retired KP physician who has had prostate cancer for 16 years.)