GENETIC-HETEROGENEITY OF NEUROBLASTOMA STUDIED BY COMPARATIVE GENOMICHYBRIDIZATION

Comparative genomic hybridization (CGH) analysis was performed on 36 n euroblastomas of both low and high stage of disease. This study signif icantly increases the number of neuroblastoma tumors studied by CGH. A nalysis of larger series of tumors is particularly important in view o f the different clinical subgroups that are recognized for this tumor. The present data and a comparison with all published CGH data on neur oblastoma provide further insights into the genetic heterogeneity of n euroblastoma. Stage 1, 2, and 4S tumors showed predominantly whole chr omosome gains and losses. A similar pattern of whole chromosome imbala nces, although less frequent, was observed in stage 3 and 4 tumors, in addition to partial chromosome gains and losses, An increase in chrom osome 17 or 17q copy number was observed in 81% of tumors. The most fr equent losses, either through partial or whole chromosome underreprese ntation, were observed for 1p (25%), 3p (25%), 4p ( 14%), 9p (19%), 11 q (28%), and 14q (31%). The presence of 3p, 11q or 14q deletions defin es a genetic subset of neuroblastomas and contributes to the further g enetic characterization of stage 3 and 4 tumors without MYCN amplifica tion (MNA) and 1p deletion. The present study also provides additional evidence for a possible role of genes at 11q13 in neuroblastoma. In a few cases, 1p deletion or MNA detected by FISH or Southern blotting w as not found by CGH, indicating that the use of a second, independent technique for evaluation of these genetic parameters is recommended. ( C) 1998 Wiley-Liss, Inc.