Abstract Background: ERG (ETS regulated gene) protein expression has been shown to reflect ERG genomic rearrangements in prostate cancer (PCA). However, ERG protein expression prognostic value has not been yet investigated. Design: ERG protein expression was investigated in a cohort of 312 men with PCA diagnosed in transurethral resection of the prostate. Results: ERG expression was detected in 76/293 (25.9%) of patients. Overall ERG expression was associated with Gleason score (GS) (p < 0.0001), tumour volume (p = 0.04) and with cancer specific mortality (p = 0.15). Low ERG intensity was significantly associated with higher GS (p = 0.02) and marginally with cancer specific mortality (p = 0.11). The association with caner specific mortality was more significant in patients without any hormonal manipulation (p = 0.02). Multivariate Cox model using GS, tumour volume and ERG intensity to predict time to cancer specific death yielded a marginally significant effect for high versus low ERG protein expression (hazard ratio (HR) = 0.36; 95% confidence interval (CI): 0.10-1.38; p = 0.14) and a non-significant effect for GS >7 (HR = 4.85; 95% CI: 0.48, 48.65; 0959-8049/$ -see front matter
