Evolution of isolated high-grade prostate intraepithelial neoplasia in a Mediterranean patient population.

The discovery of high-grade prostatic intraepithelial neoplasia (HGPIN) in prostatic needle biopsies is of clinical importance. Previous studies have shown prostate cancer to develop in 27-100% (average 55%) of the cases after HGPIN was diagnosed. Our preliminary findings in a Mediterranean population (Barcelona, Spain) revealed a prevalence of HGPIN of 4.4%, and an incidence of prostate cancer of 28.7% in cases in whom isolated HGPIN was identified at the first biopsy. The majority (64%) of these cases were diagnosed at the first biopsy after HGPIN diagnosis, and 52% within the first year. HGPIN persisted in 46.6% of the cases. The total mean serum prostate-specific antigen (PSA) was 9.9 +/- 6.6 ng/ml in the prostate cancer cases, compared with 8.8 +/- 7.5 in the cases without cancer. The low incidence of isolated HGPIN and subsequent cancer occurrence may be due to local factors or insufficient follow-up.