e16019 Background: Several signal transduction pathways,important for apoptosis and angiogenesis were idendified and their expression and correlation with survival was studied by IHC in archival prostate cancer biopsies. All pts has androgen deprivation for stage D2 disease and were followed at 3 month intervals. Methods: In an IRB approved study,42 pts had adequate tissue preserved between 1992 and 2006 and their charts were reviewed retrospectively.IHC stains to detect tumor expression of S6(ribosomal),p70s6,pTEN,AKT-1,BCL-1(Cyclin D1),VEGF,c-KIT,PDGFR-alpha and PDGFR-beta were performed by US Labs(Irvine,CA).All results were independently evaluated by two pathologists.Immunoreactivity was scored using a semiquantitative system combining intensity of staining(0–3+) and percentage of cells staining positive(0–3+).The total score was obtained by adding the scores for indensity and the percentage of positive cells,then averaging the resuts obtained by each reader.For the purpose of this study, stain intensity of 0–1+ was considered negative and the intensity of 2–3+ was considered positive.A Cox regression survival model for each stain was developed with variables known to predict survival :Gleason score,Hemoglobin(Hgb),Alkaline Phosphatase(Alk Phos),Prostate Specific Antigen(PSA),Lactate Dehydrogenase(LDH) levels. Results: The median values were: age 70yrs(56–92),Gleason score 8(6–10), LDH 171 IU/L(97–350),Hgb 12.9gm/dl (6.8–16.3), PSA 188ng/ml(2–5677),Alk Phos 139U/L(60–1756),survival 851 days(163- 6102).In univariate analysis,VEGF staining was predictive of survival (p<0.037) but not in multivariate analysis.The pTEN staining correlated with survival (p<0.0367) and a hazard ratio of 0.040 in multivariate analysis. Conclusions: In this small sample of pts, overexpression of S6,p70s6,AKT-1,BCL-1,VEGF,c-KIT,PDGFR-alpha and PDGFR-beta by IHC staining did not predict survival independently.The pTEN staining,however was strong predictor of survival in the multivariate analysis. No significant financial relationships to disclose.
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