Prevalence of high-grade prostatic intraepithelial neoplasia in prostate gland of Korean men: comparisons between radical prostatectomy and cystoprostatectomy.

OBJECTIVES

To evaluate the prevalence of high-grade prostatic intraepithelial neoplasia (HGPIN) and its association with prostate cancer in Korean men.

METHODS

A total of 160 patients who underwent radical prostatectomy for clinical prostate cancer were included as study subjects and 29 patients who underwent radical cystoprostatectomy for muscle-invasive bladder cancer were included as controls. Each intact prostate gland was serially sectioned at 3-mm intervals perpendicular to the posterior surface. The presence and prevalence of prostate cancer and HGPIN were assessed and their association evaluated.

RESULTS

High-grade prostatic intraepithelial neoplasia was present in 81 (70.4%) of 115 patients who underwent radical prostatectomy and in 8 (27.6%) of 29 patients who underwent cystoprostatectomy. This difference was statistically significant (P <0.001). Among the patients who underwent cystoprostatectomy, HGPIN was present in 5 (33.3%) of 15 patients with prostate cancer and in 3 (21.4%) of 14 patients with no evidence of prostate cancer. The presence of HGPIN had no correlation with prostate-specific antigen level, disease stage, tumor volume, grade, lymphovascular invasion, or surgical margin status.

CONCLUSIONS

The prevalence of HGPIN in Korean men with clinical prostate cancer was as great as that of Western men. Previous studies, and our results, had demonstrated a lower prevalence of HGPIN in Asian men who underwent cystoprostatectomy. The different prevalence of HGPIN found in incidental prostate cancer, between Asian and Western men, suggests that factors could be preventing the progression of prostate cancer or different characteristics of the prostate cancer in Asian populations.