Loss of chromosome 13 is the most frequent genomic imbalance in malignant fibrous histiocytomas - A comparative genomic hybridization analysis of a series of 30 cases

Regional chromosome localizations of DNA copy number imbalances were studie d by comparative genomic hybridization in 30 malignant fibrous histiocytoma s: 13 primary tumors (2 myxoid, 9 storiform pleomorphic, and 2 with more un differentiated phenotype) and 17 local recurrences (2 myxoid, 11 storiform pleomorphic, and 4 with more undifferentiated phenotype). Abnormal comparat ive genomic hybridization (CGH) profiles were observed in 25 tumors (83%). The most frequent gains (ratio >1.2) corresponded, by order of frequency, t o entire Xp, and bands 1q21, 19q13.1, 19p13, 5p13-p14, 1p31, 17p, 18p, 20q, 1p35, 17q23, and 22q12. High levels of gains (ratio >1.5) rr ere recurrent ly detected for Xp (10 cases), and in bands 1q21-q22 (8 cases), 3q27 (4 cas es), 5p13-p14 (3 cases), 13q32-q34 (3 cases), 15q22-q26 (3 cases), and 17p1 1-p12 (3 cases). Losses of 13q12-q14 or 13q21 were observed in a large prop ortion of tumors (17 cases), suggesting that a gene localized in this regio n could act as a tumor suppressor gene. Losses of 11q23, 2q32, 11p13, 10p, 1q4, 9p2, 16q12, 4q3, 10q25, 3p23, 2p24, and 12p were also recurrently obse rved. Taken together these results provide an overview of chromosome imbala nces present in MFH, which could be of use for diagnostic purposes. They po int to various chromosome regions which may harbor genes important for mali gnant fibrous histiocytomas (MFH) oncogenesis and progression. (C) Elsevier Science Inc., 1999. All rights reserved.