Commentary on screening for neuroblastoma in Japan

Abstract

Professor Sawada and his Japanese colleagues are to be congratulated on their pioneering work in establishing the feasibility of whole population screening for the detection of neuroblastoma. There can be no doubt that a successful screening program would be very welcome for a disease which continues to have a most miserable outcome when it is detected in advanced stages. The review by Sawada shows (clearly that even when methods are not standardized screening is possible across the whole of Japan. We and others have followed the Japanese example and shown that whole population screening can be undertaken and that cases of neuroblastoma can be detected. Why then did a US expert committee and the International Pediatric Oncology Society recommend that there is insufficient evidence to justify the universal implementation of neuroblastoma screening and that more research is needed? The results presented by Sawada would appear to provide convincing evidence that screening is both possible, effective, worthwhile and cost effective. What then are the problems? The key problem in attempting to study the problem is the heterogeneous nature of neuroblastoma itself. It has long been known that spontaneous regression of neuroblastoma does occur. The clearest evidence for this is stage IVs neuroblastoma, for which the current recommendation for treatment is to do as little as possible. No therapy usually leads to a favorable outcome. The occasional finding of an ‘incidental’ neuroblastoma, usually asymptomatic, during radiological or other imaging procedures, the regressed ganglioneuroma of the adrenal gland found at routine autopsy of the elderly and the finding of ‘in situ’ neuroblastoma in the adrenal glands of routinely autopsied babies at a rate of 1 : 250-400 are further evidence that spontaneous regression must occur. Sawada states in his review that in the cities of Kyoto and Sapporo the detection of neuroblastoma by screening increased from 1 : 8000 to 1 : 4000 after a very sensitive HPLC screening method was