The US Preventive Services Task Force has recommended against routine PSA screening in men for prostate cancer. The recommendation was based on the conclusion that there is moderate or high certainty that the service has no net benefit or that the harms outweigh the benefits. Large studies had revealed either no or very small increases in survival from screening in patients followed for over ten years. In a European study, results showed that in men aged 55-69, screening prevented only 7 deaths per 10,000 men followed over 9 years. In older men, screening is even less useful. Moreover, screening often leads to prostate biopsy with negative results, with complications of pain, infection and bleeding. Subsequent elevated PSA readings lead to additional biopsies with further complications. I have seen patients who had three prostate biopsies performed, all negative for cancer.
The incidence of cancer within the prostate is high, and increases with age. A 50 year-old man has about a 50% chance of having cancer in the prostate, while an 80 year-old man has an 80% chance. Many of these cancers, however, are indolent, do not metastasize, and will not cause death if untreated. Unfortunately, we have no easy way of determining early which individuals have aggressive cancer.
How will this recommendation translate into action in the real world? Will patients not want to have a PSA test? Will doctors recommend against it? Will insurance companies refuse to pay for it? Will lawsuits occur when patients who were not screened develop invasive cancer and die? I think it is unlikely that PSA screening will drop into obscurity, especially when it is compared to the ritualistic frequency of mammography screening, which the Task Force has recommended not be initiated until the age of 50, then performed every two years until the age of 75, and discontinued.
PSA testing is still valuable as a means of following the course of prostate cancer. I follow a number of men with known or presumed prostate cancer whose PSA levels have not changed over years. As long as the PSA stays the same, it is unlikely that prostate cancer is progressing. We continue to work with lifestyle changes to prevent progression, including a low fat, low animal protein, weight reduction diet, alcohol avoidance, and specific supplements including sulforaphane, lycopene, vitamin C, and modified citrus pectin.
Another test, called the PCA3, is useful in determining whether an elevated PSA indicates prostate cancer. Urine is collected after the physician performs a vigorous massage of the prostate. A negative study indicates prostate cancer is unlikely despite the high PSA, and that prostate inflammation or enlargement is the underlying abnormality.
Prostate cancer is diagnosed in 200,000 men yearly, and 30,000 men die from it. Treatments are increasingly effective, and less toxic than treatments for many other types of cancer. We have not seen a death from prostate cancer in the last ten years.