Figure 1

Chromogenic in situ hybridization (CISH) with the MYCN probe. (a) Poorly differentiated neuroblastoma with the MYCN copy number of 3.01. (b) Undifferentiated neuroblastoma with MYCN clusters. (c) Metastatic MYCN-amplified neuroblastic cells of undifferentiated neuroblastoma in bone marrow before, and (d) after cytotoxic treatment.