TRISOMY-8 AND TRISOMY-20 IN DESMOID TUMORS

A nonrandom occurrence of trisomy 8 and of trisomy 20 in desmoid tumor s has been recently reported. The finding of trisomy 8 in nondividing desmoid tumor cells by in situ hybridization prompted us to evaluate, in a similar way, the occurrence of trisomy 20 and the possible occurr ence of both trisomies together because their co-existence was cytogen etically observed in a few cases. Double fluorescence in situ hybridiz ation (FISH) with centromeric probes for chromosomes 8 and 20 was perf ormed on 16 single cell suspensions of desmoid tumors. FISH confirmed the occurrence of trisomy 8 or 20 in a single cell suspension of desmo id tumors. Both individual trisomies, and even more their association in the same cells, are rare to extremely rare in solid tumors in gener al and in mesenchymal tumors in particular, and are only known to occu r in infantile fibrosarcoma. (C) Elsevier Science Inc., 1996