PSA Doubling Time, Gleason Grade Predict Metastases

CHICAGO—Men with biochemical recurrence of prostate cancer after radical prostatectomy are more likely to develop distant disease if they present with a tumor that has a high Gleason grade or if they have a prostate specific antigen doubling time (PSADT) less than 12 months, Christopher Amling, MD, said at the 98th Annual Meeting of the American Urological Association (abstract 1489).

Since Gleason grade and PSADT were such strong predictors of the development of distant metastases in this study, these factors may identify which men are at high risk for disease progression and therefore would benefit from early clinical intervention, said Dr. Amling, a commander in the US Navy, a urologist at the Naval Medical Center, San Diego, and principal investigator of the study for the Center for Prostate Disease Research (CPDR). The data were gathered from the US Department of Defense’s CPDR Multicenter National Prostate Cancer Database, a nationwide registry of men treated for prostate disease in nine military hospitals.

The study included 3,739 men who had undergone radical prostatectomy between 1988 and 2002 and who were followed for a median of 4.52 years (range 2 to 15 years). The natural history of these men was reviewed to learn whether pretreatment PSA level, Gleason score, pathologic stage, or PSADT could predict eventual disease progression to metastasis.

Overall, about 47% of men had biochemical recurrence of prostate cancer, and 7.9% of these men went on to develop clinically detectable, systemic metastases, although only 16 men died of prostate cancer. The actuarial metastasis-free survival was about 80% at 10 years. The prostate cancer specific survival was more than 90%.

Effects of Gleason Score

Analysis showed that the metastasis-free survival rate among men with biochemical recurrence declined with rising Gleason scores. After 10 years of follow-up, 80% of men with a Gleason score of 7 or less had no evidence of metastases. However, only about 70% of men with a Gleason score greater than 7 were alive after 10 years with no signs of metastatic disease.

Metastasis-free survival also dropped with shorter PSADTs. The 10-year metastasis-free survival rate was about 90% in men who had a PSADT of 12 months or more; however, it was only about 80% in men with a PSADT less than 12 months.

The men in this study reflect "patients we commonly encounter and institute treatment for," Dr. Amling said. "Gleason score and PSA doubling time are strong predictors of who will go on to develop distant disease even in a group of men who received treatment."