D’Amico criteria alone may incorrectly classify more than one third of prostate cancer (PCa) patients as having low-risk disease, according to new findings.
Daimantas Milonas, MD, of the Lituanian University of Health Sciences in Kaunas, Lithuania, and colleagues studied 248 men who had biopsy-detected low-risk PCa based on D’Amico criteria (biopsy Gleason score of 6 or less, PSA level of 10 ng/mL or less, and clinical stage T1c- T2a) and underwent radical prostatectomy (RP). Of the 248 men, 32 (12.9%) had pT3a tumors and three (1.2%) had pT3b tumors found after RP.
Additionally, tumors were upgraded after surgery in 32.7% of cases. Overall, after RP, the investigators found unfavorable PCa in 37.5% of patients who originally were identified by D’Amico criteria as having low-risk cancer, Dr. Milonas’s team reported online ahead of print in the Scandinavian Journal of Urology. The researchers defined unfavorable disease as non-organ-confined cancer (T3) and/or Gleason score of 7 or higher with any cancer stage.
The median follow-up period was 60 months. The overall biochemical relapse rate was 14.1%.
The eight-year biochemical progression-free survival rate was 83.3% for low-risk PCa and 68.2% for unfavorable PCa. Positive surgical margins and post-operative Gleason score were the most significant predictors of biochemical relapse, the investigators found.
“In conclusion, the D’Amico criteria may underestimate aggressive prostate cancer in up to 37.5% of patients,” the authors wrote. “Consequently, caution is recommended when the decision concerning treatment is based on D’Amico criteria alone.”