[Familial neuroblastoma]

Neuroblastoma (NB) is a common malignant solid tumor in childhood, accounting for about 40% of the solid children's neoplasms on the Japanese registry in 1993. It is known that some cases of NB are hereditary, but their incidence is very low. We report two patients with adrenal familial NBs and review the literature on familial NB. Two hit theory was proposed to explain the occurrence of hereditary and non-hereditary NBs. This theory supports the fact that the median age at diagnosis is much younger and the incidence of multiple primaries is higher in the familial NB than in non-familial cases. As therapy for NB improves and more children survive to adulthood, there will be more opportunity to study their offspring.