Imaging and Pathology Correlations for Different Risk Stratification Models for Intermediate-risk Prostate Cancer.

Abstract

We evaluated whether sub-stratifying intermediate-risk (IR) prostate cancer using the Memorial Sloan Kettering Cancer (MSKCC) or Prostate Cancer Risk Stratification (ProCaRS) model predicts for adverse imaging or pathologic features. 56 consecutive IR patients who underwent multi-parametric MRI (mpMRI) and radical prostatectomy (RP) were studied. The different groups were tested for correlation with adverse findings. 2-sample T-tests assuming unequal variance were used. On mpMRI the MSKCC unfavorable group had higher index lesion suspicion scores (p=0.044), while the ProCaRS model showed a higher maximum tumor diameter (MTD) in the high-risk group (p=0.047). At RP, a higher pathologic MTD (23.3 vs. 17.6 mm, p=0.005) was present in the MSKCC unfavorable group as well as the ProCaRS high vs. low group (26.6 vs. 19.3 mm, p=0.022). Both models demonstrated a correlation with higher MTD for unfavorable IR patients. This is likely a driver of worse clinical outcomes.