Genetic characterization of angiomatoid fibrous histiocytoma identifies fusion of the FUS and ATF-1 genes induced by a chromosomal translocation involving bands 12q13 and 16p11

This case report documents the first karyotypic, fluorescence in situ hybri dization, and genetic analysis of an angiomatoid fibrous histiocytoma that arose and recurred in the arm of a 5.5-year-old girl. Complex rearrangement s between chromosomes 2, 12, 16, and 17 were noted, as well as deletion in the long arm of chromosome 11. Flow cytometry revealed a normal cell popula tion. The t(12;16) site was further investigated using reverse transcriptas e-polymerase chain reaction. We found that the FUS (also known as TLS) gene from 16p11 combined with the ATF-1 gene from 12q13 to generate a chimeric FUS/ATF-1. The FUS gene is rearranged in the t(12;16(q13;p11) that characte rizes myxoid liposarcoma and in acute myeloid leukemia with t(16;21)(p11;q2 2), while the ATF-1 gene is rearranged in the t(12;22)(q13;q12) found recur rently in clear cell sarcomas (malignant melanoma of soft parts). Thus, the FUS/ATF-1 gene in angiomatoid fibrous histiocytoma is predicted to code fo r a protein that is very similar to the chimeric EWS/ATF-1 found in clear c ell sarcoma. (C) 2000 Elsevier Science Inc. All rights reserved.