Risk of unfavorable character among neuroblastomas detected through mass screening. The Japanese Infantile Neuroblastoma Cooperative Study.

Current study shows that about 50% of neuroblastomas (NBs) detected through mass screening had factor(s) indicating an unfavorable biological nature and that early intervention after the screening might improve clinical outcome of the patients. On the other hand, favorable properties were detected in the remaining half of the mass-screening NBs. Some of them might have the ability to regress spontaneously. Therapeutic modality should be determined according to their biological nature. Further investigation for their biologic properties is necessary to evaluate the benefits of the mass screening.