Fig. 1

Typical fluorescence in situ hybridization (FISH) images of bone marrow cells from patients with bone marrow metastatic neuroblastoma. a The status of v-myc avian myelocytomatosis viral oncogene neuroblastoma derived homolog (MYCN) amplification was detected using a dual-color probe. Green signals represent the specific probe for MYCN, and red signals stand for centromeric chromosome 2 probes. MYCN signals show more than 10 copies within the nuclei. b The status of 11q23 deletion was also detected using a dual-color probe. Normal cells show a two orange/green fusion signal pattern. In a cell with 11q23 deletion, the pattern is one orange/green fusion signal