[High incidence of chromosome 8 monosomy and chromosome 7 trisomy in prostatic primary tumor and its related lymphatic metastasis. Preliminary results]. / Alta incidencia de la monosomia del cromosoma 8 y la trisomia del cromosoma 7 en el tumor primario prostático y su metástasis ganglionar asociada. Resultados preliminares.

INTRODUCTION: The research on tumoral aggressivity parameters in prostate cancer, such DNA ploidy detected by fluorescence in situ hybridization, has significant relevance to refine prognostic on an individualized patient. OBJECTIVES: To identify chromosome numeric alterations by FISH in primary prostate cancer focus and its corresponding lymph node metastases. b) To describe a cytogenetic tumoral progression pathway. METHODS: So far, we have retrospectively studies eight patients with prostate cancer and lymph node metastases performing FISH analysis on the primary prostate cancer focus and its metastatic lymph node. DNA probes for chromosomes 7, 8, 10 and 12 have been used for FISH analysis. RESULTS: a) Seven out of eight tumours (85%) were aneuploid when studied by FISH and the most frequent chromosome alterations found were monosomy 8 (100%) and trisomy 7 (85.7%). All the lymph nodes were aneuploid being monosomy 8 (87.5%) and trisomy 7 (62.5%) the most common chromosome alterations. b) Monosomy 8 and trisomy 7 appeared to be in the same cytogenetic tumoral progression pathway. CONCLUSION: Although we report about a preliminary study, monosomy of chromosome 8 and trisomy 7 are related with poor evolution, probably because of the loss of a suppressor gene or a proto-oncogen overexpression. The presence of any of them in a prostate cancer focus is related with poor prognosis.