Neuroblastoma screening data. An epidemiologic analysis

Neuroblastoma is one of the most common malignant neoplasms in children under age 5 years. Little progress has been made in the prognosis of advanced stage disease in the past three decades. Since the development in the 1960s of a simple urine test to detect neuroblastoma metabolites, there has been hope that mortality from this disease could be reduced by early detection via mass screening of young infants. Encouraging reports from Japan on mass screening programs instituted in the 1970s have been appearing in the medical literature since 1982, resulting in widespread interest in screening. This article applies standard epidemiologic criteria for screening evaluations to the Japanese reports. We find that the data needed to definitively assess the value of screening were not a part of those reports and that the benefits claimed from the reported data could be due to overdiagnosis. In addition, the most recent Japanese data, combined with recent advances in biologic understanding of neuroblastoma, show that screening at age 6 months may not detect tumors with poor prognoses. Even if it could, it is uncertain whether those outcomes could be substantially altered by earlier diagnosis. Although a final verdict on the value of neuroblastoma screening is not yet possible, these neuroblastoma studies are an excellent example of how screening results must be viewed with extreme caution in the absence of age-specific, population-based incidence and mortality rates.