Long-term effects of mass screening for neuroblastoma in infancy

Eighty-four neuroblastoma patients were treated at the Department of Pediatrics, Kyoto Prefectural University of Medicine, during the 27 years from 1962 to 1988. They were divided into three groups: 35 cases in phase 1, the 12 years before mass screening from 1962 to 1974; 22 in phase 2, the 8 years after the onset of mass screening by a qualitative vanillylmandelic acid (VMA) test from 1974 to 1982; and 27 in phase 3, the recent 6 years from 1983 to 1988, after the introduction of mass screening by quantitative assay for VMA and homovanillic acid using high performance liquid chromatography. The clinical findings of these patients were compared for each phase. In Kyoto, the number of annual neuroblastoma cases diagnosed under 1 year of age increased from 0.58 in phase 1 to 1.50 in phase 2 and 3.17 in phase 3. The number of cases over 2 years of age decreased from 2.00 in phase 1 to 0.88 in phase 2 and 1.00 in phase 3. Survival rates increased from 17.1% (six of 35) in phase 1 to 54.5% (12 of 22) in phase 2 and 85.2% (23 of 27) in phase 3. The annual number of neuroblastoma deaths decreased from 2.42 in phase 1 to 1.25 in phase 2 and 0.67 in phase 3. Mass screening for neuroblastoma in infancy has increased the long-term survival rates of neuroblastoma cases treated at this hospital.