CD34 IMMUNOHISTOCHEMICAL ASSESSMENT OF ANGIOGENESIS AS A PROGNOSTIC MARKER FOR PROSTATE-CANCER RECURRENCE AFTER RADICAL PROSTATECTOMY

Purpose: We assess the neovascularity of clinically localized prostate cancer by immunohistochemistry using the monoclonal antibody CD34 in an attempt to identify associations between angiogenesis and disease p rogression following radical prostatectomy. Materials and Methods: Mic rovascularity was evaluated using the CD34 monoclonal antibody in arch ival paraffin embedded radical prostatectomy specimens from 149 patien ts followed from 3 to 10 years (mean 6.6). Vessels were quantified by counting a minimum of 2 selected microscopic fields (200x, 0.754 mm.(2 )) from each tumor, area of prostatic intraepithelial neoplasia and pr ostatic hyperplasia, and given a numerical value representing the micr ovessel density count.Results: Mean microvessel density count did not vary significantly with age or race. There was a significant associati on between the count and nuclear grade, Gleason sum and pathological s tage. Cox survival analysis shows that microvessel density is signific antly related to time to recurrence when considered as a continuous va riable (p = 0.03) as well as dichotomous variable (p = 0.007) (microve ssel density count less than 90 and 90 or greater). The 5-year recurre nce-free survival was significantly higher for patients with a count l ess than 90 (71%) than for those with a count 90 or greater (51%) (p = 0.006). The 5-year recurrence-free survival was also significantly di fferent when microvessel density was used as a continuous variable (p = 0.02). Controlling for stage, Gleason sum, race and nuclear grade, m icrovessel density remained significant in predicting recurrence (p = 0.03) but when pretreatment prostate specific antigen was included in the model the count was no longer significant. The microvessel density count in the tumor area significantly increased with increasing Gleas on sum and nuclear grade but it did not increase significantly in the adjacent benign prostate or areas of prostatic intraepithelial neoplas ia in the same specimen. Conclusions: Microvascularity or neovasculari ty as measured by the CD34 antigen may be a prognostic marker of recur rence for prostate cancer patients after radical prostatectomy but mor e study in prostate specific antigen era patients with sufficient foll owup is needed.