Objectives: To determine whether race is an independent predictor of positive surgical margins in patients who undergo radical prostatectomy.
Methods: Radical prostatectomies were performed on 750 patients at five Veterans Affairs hospitals: Shreveport, Louisiana (n = 451), Houston, Texas (n = 92), Jackson, Mississippi (n = 83), New Orleans, Louisiana (n = 69), and Little Rock, Arkansas (n = 55). All men who did not receive neoadjuvant hormonal therapy and for whom complete follow-up data were available were included in the analysis (of 607, 260 were African-American and 347 were white). Multiple logistic regression analysis was used to determine the significance of race as an independent predictor of surgical margin status after radical prostatectomy for clinically localized prostate cancer.
Results: After controlling for clinical stage, Gleason grade, and preoperative prostate-specific antigen (PSA), multivariable logistic regression analysis revealed that race was not an independent predictor of positive surgical margins (P = 0.9). Of the variables evaluated, both preoperative PSA (P = 0.0005) and biopsy Gleason grade (P = 0.047) were significant predictors of an increased risk of a positive surgical margin.
Conclusions: Positive surgical margins are a widely accepted surrogate marker of increased biologic potential in patients with prostate cancer. In our study population, race was not an independent predictor of surgical margin status. Coupled with observations that survival is not related to race, this finding suggests that the biology of prostate cancer in African-American and white men is similar and that observed racial differences more likely are due to ethnic factors that influence tumorigenicity.