TRISOMY-20 IS A PRIMARY CHROMOSOME ABERRATION IN DESMOID TUMORS

Cytogenetic analysis revealed trisomy 20 in 4 desmoid tumors: in 2 cas es as the sole aberration, in 1 together with +X, -Y and -13 and in 1 with +8 and a supernumerary marker chromosome. Our findings indicate t hat gain of chromosome 20 is an early event in the development of a la rge subset of desmoid tumors and that it is as frequent as +8, the onl y consistent chromosomal change previously reported in this tumor type . The non-random occurrence of trisomies 8 and 20 in desmoid tumors in dicates shared pathogenetic mechanisms with infantile fibrosarcoma, a fibrous tissue tumor characterized by various combinations of trisomie s for chromosomes 8, 11, 17 and 20. (C) 1995 Wiley-Liss, Inc.