A report in the April 4 issue of the Journal of the National Cancer Institute authored by Swedish researcher Dr.Katja Fall indicates PSA (Prostate Specific Antigen ) blood testing may be a poor tool for use in men who do not have to be treated for prostate cancer but are placed under "watchful waiting" by their doctors.
Because prostate cancer progresses slowly, doctors often use the 'watchful waiting' method when a tumor is found in the prostate. A rise in the PSA level usually indicates a tumor has gone from benign ( harmless ) to malignant (dangerous ).
This study led by Dr.Fall involved 267 men who were found to be in the early stages of prostate cancer. These men were not treated for their cancer, but they were closely followed to see if their cancer was progressing. This study was performed over a 2 year period.
Initial PSA values and the rate of change were associated with later development of cancer, the researchers reported. However, PSA readings were found to "perform poorly in distinguishing between those who develop a lethal prostate cancer from those at low or no risk of disease progression," they wrote.
Dr. Anthony D'Amico of Harvard Medical School was quick to criticize these findings. Dr.D'Amico said this study has far too short of a follow-up period in which to make solid conclusions about the PSA test. It should be noted that Dr.D'Amico led a team in which his research showed the PSA is
a good test in predicting serious trouble. Dr.D'Amico's reasearch was performed 2 years ago.
Dr.D'Amico feels that because only 13 percent (34 ) of the men in Dr.Fall's study died from prostate cancer; a conclusion about what would happen to the other 87 percent of men in this study would not be valid.
Dr. Fall countered by saying his study shows a non-PSA test needs to be developed as another tool in helping doctors decide the best treatment plan for their patients.