Development of a needle biopsy-based genomic test to improve discrimination of clinically aggressive from indolent prostate cancer.

4560 Background: Standardized, quantitative tools are needed to improve discrimination of clinically aggressive from indolent prostate cancer at diagnosis. We previously identified multiple genes and biological pathways in radical prostatectomy (RP) specimens associated with clinical recurrence and adverse pathology. We evaluated whether measurement of these genes in prostate needle biopsy (Bx) specimens predicts adverse pathology - high grade (GS ≥ 4+3) and/or non-organ-confined disease (pT3) - in a separate study of AUA low-intermed risk pts treated w/ RP. Methods: All AUA low-intermed risk (cT1-T2a, GS 3+3/3+4) pts treated w/ RP <6 mos from Bx at Cleveland Clinic (1999-2007) w/ available Bx tissue and <3 pos cores were evaluated. Expression of 81 prognostic genes identified in previous RP studies and 5 reference genes was quantitated by RT-PCR in 60 µm manually microdissected FPE prostate needle Bx tissue. Association of gene expression w/ adverse pathology was analyzed by logistic regression controlli...