DO PROSTATE-SPECIFIC ANTIGEN AND PROSTATE-SPECIFIC ANTIGEN DENSITY ENHANCE THE DETECTION OF PROSTATE CARCINOMA AFTER INITIAL DIAGNOSIS OF PROSTATIC INTRAEPITHELIAL NEOPLASIA WITHOUT CONCURRENT CARCINOMA

BACKGROUND. Prostatic intraepithelial neoplasia (PIN) is considered to be a precursor of prostate carcinoma in which serum levels of prostat e specific antigen (PSA) have been correlated with PIN grades. The aim of this study was to determine whether PSA and prostate specific anti gen density (PSAD), obtained at the time of initial diagnosis of PIN w ithout concurrent carcinoma, can be used as predictive factors to disc riminate patients with subsequent cancer on repeat biopsy. METHODS. We studied, retrospectively, the records of 93 patients with PIN (low an d high grade) without concurrent carcinoma at the time of their first needle biopsy. We assessed the relationship between initial PIN grade, PSA, and PSAD with later detection of carcinoma on repeat biopsy. Pat ients were divided into 3 subgroups for analysis according to their in itial PSA level (0-4, 4.1-10, > 10 ng/mL). RESULTS. Carcinoma detectio n rate on repeat biopsy was 13.3% for patients with low grade PIN and 47.7% for patients with high grade PIN (P < 0.006). High grade PIN was frequently associated with subsequent carcinoma whatever the PSA leve l (33.3-61.9%). Low grade PIN was associated with subsequent carcinoma in 42.8% of the cases when PSA was greater than 10 ng/mL. When PSA wa s between 4 and 10 ng/mL, low grade PIN carcinoma was found on repeat biopsies in only 10.7% of the cases (P = 0.05). In none of the PSA sub groups did PSAD enhance later cancer detection. CONCLUSIONS. For patie nts with high grade PIN, the incidence of subsequent carcinoma is high , whatever the PSA values. For these cases repeat biopsies should be r ecommended. Patients with low grade PIN and PSA greater than 10 ng/mL should have repeat biopsies because the incidence of subsequent carcin oma is high and comparable to high grade PIN. PSAD did not provide add itional information. (C) 1996 American Cancer Society.