CHROMOSOMAL-ANOMALIES IN STAGE D1 PROSTATE ADENOCARCINOMA PRIMARY TUMORS AND LYMPH-NODE METASTASES DETECTED BY FLUORESCENCE IN-SITU HYBRIDIZATION

Purpose: We determined if characteristic chromosomal anomalies exist w ithin the primary tumors and lymph node metastases in patients with st age D1 prostate cancer, and compared the patterns of chromosomal alter ations between primary tumors and nodal metastases. Materials and Meth ods: Fluorescence in situ hybridization analysis using peri-centromeri c probes for chromosomes 6, 7, 8, 17, X and Y was performed on 5 mu. s ections from paraffin embedded tissue blocks obtained from 23 consecut ive patients who underwent radical prostatectomy and bilateral pelvic lymphadenectomy in 1990 for stage D1 prostate cancer. Results: The dom inant focus of primary tumor was compared to matched nodal metastases in 12 cases. Five of 12 primary tumor foci (41.7%) had similar chromos omal gains and the same fluorescence in situ hybridization ploidy resu lt as the corresponding nodal metastases. Chromosomes 7 and X (73.2% o f cases) were most frequently gained in the primary tumors, and chromo somes X and Y (81.2% of cases) were most frequently gained in the meta stases. No primary tumor or metastasis demonstrated chromosomal loss. Three of 19 primary tumors (15.7%) were diploid, while 16 of 19 (84.3% ) were nondiploid. Chromosomal aneusomy was inversely correlated with increasing Gleason summary score. Conclusions: These data indicate tha t the dominant primary tumor foci may not give rise to nodal metastase s, gains of chromosomes 7, X and Y may be associated with metastatic b ehavior, and patients with stage D1 disease have a greater rate of ane uploidy than those with lower stage cancer.