To assess the performance characteristics of prostate-specific antigen (PSA) for predicting the volume of total or high-grade cancer in men undergoing radical prostatectomy. It is known that the performance characteristics of PSA are improved for predicting the presence of high-grade prostate cancer.

We identified 1459 patients from the Stanford Radical Prostatectomy Database with clinical Stage T1c (n = 783) and T2 (n = 676) disease who underwent surgery from 1988 to 2003 with detailed morphometric mapping. We generated receiver operating characteristic curves for PSA levels according to the total and high-grade (Gleason score 4 or 5) cancer volume and compared the areas under the curve (AUC) for the various total and high-grade cancer volumes.

For patients with Stage T1c disease, the AUC for the PSA ROC curve increased in a stepwise fashion as both the total cancer volume and the high-grade cancer volume increased. Significant differences between the AUCs for low and high volumes of total and high-grade disease were observed. For T2 disease, the AUCs for predicting high-grade cancer volume were generally greater than the corresponding AUCs for T1c disease, although no incremental increase was observed.

In patients with Stage T1c disease, in whom the PSA level was the driving force for biopsy, the PSA performance improved in a stepwise fashion with greater total and high-grade cancer volumes as evidenced by improved ROC. Previous studies have shown that PSA performs better for detecting the presence of high-grade disease. We have shown that PSA performs better in predicting greater volumes of high-grade disease in radical prostatectomy specimens.