A Validated Whole-Blood Rna Transcript-Based Prognostic Model That Predicts Survival In Men With Castration-Resistant Prostate Cancer

4516 Background: Survival for patients with castration resistant prostate cancer (CRPC) is highly variable. We developed a whole blood RNA transcript-based model as a prognostic biomarker in CRPC. Methods: Peripheral blood was collected from 62 men with CRPC in a training set and from 140 patients with CRPC in a validation set on various treatment regimens. A panel of 168 inflammation and prostate cancer-related genes was evaluated using optimized quantitative polymerase chain reaction to assess biomarkers predictive of survival. A 2-class proportional hazard model was developed from time of CRPC diagnosis and time of blood draw. Results: A 6-gene model (consisting of ABL2, SEMA4D, ITGAL, and C1QA, TIMP1, CDKN1A) separated CRPC patients into two classes: higher risk men who died within 2·2 years of developing CRPC and lower risk men who lived over 2·2 years (log rank p=0·00083). The results were similar regardless of the survival time definition (CRPC diagnosis versus blood draw) and did not depend on whe...