MP69-19 VARIATION IN THE FREQUENCY OF PREMALIGNANT LESIONS AMONG PATIENTS UNDERGOING PROSTATE BIOPSY IN MICHIGAN

Abstract

performed to model the most parsimonious and accurate combination of clinical characteristics predicting the presence of UD at final pathology. RESULTS: Overall, 320 (15.4%) patients met the criteria to be enrolled. Mean number of cores taken was 16 (median 14). However, 89 patients (27.8%) harboured UD at final pathology. When PSA, PSA density or clinical stage were excluded from the criteria, only few more patients could be enrolled [+39 pts (+12.2%), +25 (+7.8%) or +2 (+0.6%), respectively] and virtually the same prevalence of patients harboured UD (26.5% vs. 28.1% vs. 27.6%, respectively; p1⁄40.8). When GS was excluded, 360 more patients could be enrolled [+40 (+12.5%)], although this led to a higher prevalence of UD (119/360, 33.1%; p1⁄40.03). Similarly, when number of positive cores was excluded, 887 patients [+567, +177.2%] patients fulfilled the criteria but up to 35.7% (317/887) harboured UD. In the most parsimonious model (biopsy GS 6 and percentage of positive cores <20%), 430/2077 (+110 pts, +34.4%) patients could be enrolled for AS with virtually the same proportion of UD (117/430, 27.2%) relative to the full 5-variables criteria proposed by Van De Bergh (27.8%; p1⁄40.9). CONCLUSIONS: Percentage of positive cores and GS at diagnosis and are the most informative variables that may help in select candidates for AS protocols. We proposed a user-friendly 2-variables tool to extend AS to one third more of contemporary PCa patients without compromising cancer control.