To investigate retrospectively the clinical and biological features that influence the outcome of infants with neuroblastoma (NB) detected by mass screening (NBMS), and to construct surgical strategies to deal with NBMS, 20 infants diagnosed as having either NB or ganglioneuroblastoma (GNB) between 1986 and 1998 were enrolled in a study. They comprised 15 boys and 5 girls ranging in age from 7 to 14 months. The following factors were analyzed by multivariate analysis: age, stage according to the Japanese staging system at the time of diagnosis, site of the primary tumor, histologic findings, preoperative urinary vanillylmandelic acid (VMA) and homovanillic acid (HVA) levels, VMA/HVA ratio, lactate dehydrogenase, neuron-specific enolase, Shimada's histologic classification, amplification of the N-myc oncogene by Southern blot analysis, nuclear content, and chromosomal abnormality. The 2-year survival was 95.0% (19/20). The site of the primary tumor was the adrenal gland in 12 cases, retroperitoneum in 6, and retrothoracic space in 2. Four infants had stage 1, 6 stage II, 3 stage III, 3 stage IVB, and 4 stage IV disease. Complete resection was achieved in all cases except for I retroperitoneal GNB. Histologic examination showed that 8 patients had NB. Of the 12 GNBs, 8 were poorly-differentiated and I was well-differentiated. Only I of the 14 examined tumors showed amplification of N-myc (20 copies). The infant with N-myc-positive NB (stage II) died 23 months after surgery in spite of aggressive postoperative chemotherapy. Multivariate analysis revealed the plasma NSE level to be a significant predictor of survival (p < 0.0143). This suggests that N-myc amplification and plasma NSE level could be closely related to the survival of infants with NBMS. The N-myc-positive NB case implies that even in locoregional NB detected by NBMS, surgical excision should play a central role in the diagnosis of its oncogenic characteristics and indicate any subsequent therapy.
