Evaluation of early clinical experience of a novel prognostic proteomics prostate cancer biopsy test.

88 Background: Standard clinical and pathological parameters derived from diagnostic biopsy are insufficient to accurately assess final prostate tumor pathology of patients with biopsy Gleason grades 3+3 or 3+4. We developed a novel assay (ProMark) that performs quantitative measurements of 8 protein markers from prostate biopsy FFPE sections. In the validation study, assay risk scores were strongly predictive of final prostate tumor pathology with a C-stat of 0.69 (95%CI = 0.63 – 0.76) (p<0.0001). By design, the train-test (N=381) and validation (N=274) studies were enrichment studies, with a higher % of aggressive disease than in the intended use population. Here we study 293 needle biopsy cases that have come to our CLIA lab for ProMark testing over a four month period. The objective of this study is to establish the ProMark score distribution for these ‘real world’ clinical use patients, and to confirm that this distribution matches our clinical validation study. Methods: To establish prevalence of ag...