Top Line: The OncotypeDX Genomic Prostate Score (GPS) is a 17-gene assay that is prognostic of biochemical recurrence, distant metastasis, and prostate cancer mortality risk after radical prostatectomy. But how well does GPS perform at predicting outcomes of primary radiation using biopsy specimens?
The Study: This study from the Durham VA Health System ran GPS on biopsy specimens of 238 men who were treated with radiation for prostate cancer. Most patients had favorable (23%) or unfavorable (37%) intermediate risk disease followed by high risk (21%), very high risk (11%), and low risk (8%). Half of patients received ADT. The median GPS was 37. After prostatectomy, a GPS of 40 is associated with worse outcomes. In this study, 41% had a GPS >40. The risk of biochemical failure was 3 times higher for those with GPS >40 (32% v 11%). Likewise, the rate of DM (18% v 5%) and prostate cancer mortality (13% v 3%) were significantly higher with a GPS >40. In multivariable analysis, GPS provided additional prognostic information beyond standard clinicopathologic features and risk stratifications. This study included an impressive 69% Black patients, and GPS was prognostic of outcomes regardless of race. While this study doesn’t directly inform us about treatment intensification, the risk of adverse outcome after radiation identified by GPS may help tailor treatment intensity (nodal coverage or ADT) for individual patients.
TBL: OncotypeDX GPS is prognostic of treatment outcome after definitive radiation for prostate cancer across risk categories. | Janes, Int J Radiat Oncol Biol Phys 2022