Malignant gliomas occurring in identical twins.

The occurrence of malignant gliomas in a pair of identical twins is reported. One, in the posterior fossa, presented in the third year of life, the other, in the left cerebral hemisphere, in the eighth. Both ran a rapidly progressive course and died within a few months of the onset of symptoms. The histological structure of the gliomas was similar and both tumours consisted of astrocytic and oligodendroglial parts. Review of the literature revealed only two pairs of histologically proven gliomas occurring in identical twins. The number of cases reported is too small for any valid conclusions on possible genetic mechanisms.