ANEUSOMIES OF CHROMOSOME-8 AND CHROMOSOME-Y DETECTED BY FLUORESCENCE IN-SITU HYBRIDIZATION ARE PROGNOSTIC MARKERS FOR PATHOLOGICAL STAGE-C (PT(3)N(0)M(0)) PROSTATE CARCINOMA

In an attempt to identify new prognostic markers, we performed fluores cence in situ hybridization (FISH) ploidy analysis of tumor tissue fro m patients with a targeted stage and histological grade of prostate ca rcinoma. We identified all 227 patients from the Mayo Clinic radical p rostatectomy data base who had a high histological grade pathological stage C (pT(3)N(0)M(0)) tumor removed between 1966 and 1987, After his tological review of the paraffin-embedded specimen blocks, 181 cases w ere suitable for FISH analysis using chromosome enumeration probes for chromosomes 7, 8, 10, 12, X, and Y. FISH detected 80 (44%) diploid, 2 2 (12%) tetraploid, and 79 (44%) aneuploid tumors. The common aneusomi es were of chromosomes 7 and 8, which were present in 51 (28%) and 46 (25%) tumors, respectively. Aneusomies of chromosomes 10, 12, X, and Y were observed in 11 (6%), 15 (8%), 12 (7%), and 16 (9%) tumors, respe ctively. FISH aneuploid tumors showed a trend of more frequent systemi c prostate cancer progression than nonaneuploid tumors (P = 0.060). Fo r individual chromosome anomalies, gains of chromosome 8, aneusomy of chromosome 8, and aneusomy of chromosome Y correlated highly with syst emic cancer progression (P = 0.006, 0.013, and 0.021, respectively). G ains of chromosome Y and aneusomy of chromosome Y were associated with an increased prostate cancer death rate (P < 0.001 for both). Multiva riate analysis showed that gains of chromosome 8 and aneusomy of chrom osome Y were significant independent ''predictors'' of systemic cancer progression (P = 0.008) and cancer death (P < 0.001), respectively. T hese results demonstrate that aneuploidy and specific aneusomies detec ted by FISH are potential markers for a poor prognosis in histological high-grade pathological stage C (pT(3)N(0)M(0)) prostate carcinoma.