Neuroblastoma mass screening: the arguments for and against.

Neuroblastoma is the second commonest malignancy in childhood. The prognosis of the disease is largely dependent on the extension of the tumour at diagnosis. For disseminated disease the survival rate is very low. The question as to whether mass screening in infants can improve the prognosis of the disease was first addressed in Japan more than 20 years ago. Since then, more than 7 million children have been screened in Japan and over 650 cases of neuroblastoma have been detected. However, the available data are compromised by an inadequate cancer registry and conclude that screening at 6 months of age seems to double the incidence of neuroblastoma. This result has been verified by a Canadian study conducted from 1989 to 1994 in the province of Quebec. The incidence of neuroblastoma appeared to have tripled, and there was no decrease in the rate of advanced disease. Mass screening pilot studies have also been conducted in the U.K., France, Austria, Australia, U.S.A., Italy, Norway and Germany. Analysis of the results shows that neuroblastoma screening before the age of 6 months is feasible, but no significant reduction in mortality could be shown until now. Moreover, most of the cases diagnosed by screening have favourable biological markers. Only a few with unfavourable parameters, such as amplification of proto-oncogene MYCN, diploidy and/or del 1p36 could be detected. A screening programme that includes 1.25-2 million screened and unscreened children at 1 year of age monitored by an almost complete national cancer registry should show whether mass screening for early detection of neuroblastoma is worthwhile.