Comparative evaluation of National Prostatic Cancer Treatment Group and Gleason systems for pathologic grading of primary prostatic cancer.

Multivariable analysis was used to investigate the relationship between risk of disease progression or death in patients who were treated with adjuvant therapy after definitive treatment for prostatic adenocarcinoma and the components of the National Prostatic Cancer Treatment Group (NPCTG) and Gleason systems for pathologic grading of prostatic cancer. Data were available for 203 patients who were treated on NPCTG Protocols 900 and 1,000, which involve surgical and radiation therapy as definitive treatment. Since less than 10 per cent of these patients have died, analysis of survival was not attempted. The study focus was progression-free survival, which is the minimum of time to progression or death. The analysis demonstrates that a new measure, the NPCTG score (the sum of the glandular and nuclear grades) is superior to the previously reported NPCTG grade (the maximum of the two grades). In addition, the Gleason score is somewhat superior to the new NPCTG score. All of this, however, applies only to the primary tumor and not the nature of any present or future metastatic lesions.