PSA after prostate surgery not always ominous

Men with prostate cancer who undergo removal of the prostate (i.e., radical prostatectomy) hope to see their PSA fall to zero, but sometimes it remains detectable in their blood. This isn't a good sign, but it bodes worse for some men than others.

"Our study shows that not all people who fail to achieve an undetectable PSA after radical prostatectomy are the same," Dr. Craig G. Rogers told AMN Health.

In particular, how fast the PSA levels rises after surgery may help identify patients who are likely to go downhill rapidly, and would therefore benefit from intensified treatment.

Rogers, in the Department of Urology at Johns Hopkins Hospital in Baltimore, and colleagues assessed the outcome of 160 men with persistently detectable PSA after they underwent radical prostatectomy for localized prostate cancer.

The PSA level is measured in nanograms per milliliter of blood, and 0.1 ng/mL is considered the lowest detectable level.

In 75 men (47 percent), the cancer spread to other sites, or "metastasized", an average of five years after surgery, the team reports in the medical journal Cancer.

However, Rogers noted, "Some patients remain free of metastatic disease for a prolonged period (7-10 years), whereas others progress rapidly to metastatic disease in less than 3 years."

According to the researchers, the rate of rise in the PSA level - known as the PSA slope - after prostatectomy can help identify patients who are at increased risk of having the disease spread.

"In particular, a PSA slope of 0.05 ng/mL per month or greater during the time period of 3-to-12 months after radical prostatectomy was particularly useful in identifying high-risk patients," Rogers told Reuters Health.

Summing up, Rogers said "the findings from this study have potential application in identifying those patients at higher risk of metastasis," and this can help doctors figure out who should get additional treatment and when.

SOURCE: Cancer December 1, 2004.