Gleason Pattern 5 is Associated With an Increased Risk for Metastasis Following Androgen Deprivation Therapy (ADT) and Radiation: An Analysis of RTOG 9202 and 9902

Limitations of the Cancer of the Prostate Risk Assessment (CAPRA) Prognostic Tool for Prediction of Metastases and Prostate Cancer-specific Mortality in Patients Treated With External Beam Radiation Therapy

“…[15][16][17][27][28][29][30] In the present study, after controlling for CAPRA score, the presence of GP-5 as the primary pattern was associated with a nearly 20-fold increased risk of death and 12-fold increased risk of metastases. Given that in the CaPSURE analysis, GS 8 to 10 disease was present in 6% of patients treated with RP versus 15% of those treated with EBRT, it is reasonable to speculate that a correspondingly higher prevalence of GP-5 would also have been present in the EBRT cohort, potentially confounding the comparison between modalities, and raising questions about the validity of the conclusions from this and other studies of comparativeness effectiveness in which the CAPRA instrument has been used for risk adjustment.…”

“…9 Similarly, CAPRA does not account for the presence of Gleason pattern 5 (GP-5), which even as a tertiary pattern is an established independent adverse prognostic factor in PC. [15][16][17] Although these limitations would not be expected to significantly impact the discriminatory ability of the CAPRA instrument to predict outcomes in surgical cohorts, which generally consist of limited numbers of patients with high-risk GS or GP-5, CAPRA is less likely to accurately discriminate risk in populations treated with EBRT, which typically have a higher prevalence of high-risk GSs. 9,11,13,14,18 The insensitivity of CAPRA to such risk differences between RP and EBRT patients may, therefore, underestimate risk in EBRT patients, and has the potential to confound results of observational studies that use CAPRA for risk adjustment between patients treated with EBRT and RP.…”