Integrated assessment of potential value of erbB-2 amplification or expression status as novel therapy target in Chinese children and adolescents with osteosarcoma. Targeted tumor therapies have been making rapid progress in recent years, and the erbB-2 oncogene is a suitable target. There was much discussion about the level of erbB-2 in osteosarcoma. The aim of this study was to investigate the erbB-2 amplification or expression status in osteosarcoma.Fluorescence in situ hybridization (FISH) and DNA probes for erbB-2 and centromere 17 were used to examine the erbB-2 gene amplification status in 32 osteosarcoma samples, and expression of erbB-2 was analyzed by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR).None of the 32 osteosarcomas was observed by FISH to have the erbB-2 gene amplified, and no distinguishable membrane staining was seen in any case yet, nevertheless, erbB-2 overexpression was present in 6 tumor samples by RT-PCR.The status of erbB-2 gene amplification and membrane overexpression is rare in osteosarcomas, and might suggest that the erbB-2 target agent should not be applied to osteosarcomas as single treatment.