Abstract

Examination of the records of cases of neuroblastoma, nephroblastoma, hepatoblastoma, and teratoma has not revealed a significant association between neoplasia and malformation. An increase in 'local' abnormalities in sacrococcygeal teratomata might be explained by local growth effects. The significance of the definition of malformation, the validity of comparisons between 'general incidence' figures for malformations, and those obtained in tumour-bearing patients is considered.