In the present study, PBSC-MRD was detected by ddPCR with different ADRN NB-mRNAs (CRMP1, DBH, DDC, GAP43, ISL1, PHOX2B, and TH mRNAs) and was significantly associated with EFS of high-risk NB patients. The gene discussed is PHOX2B; the disease is neuroblastoma.