Supratentorial recurrences of gliomas. Results of reoperations on astrocytomas and oligodendrogliomas.

On the basis of our previous investigation regarding histological transformation of recurrent astrocytomas and oligodendrogliomas we report the clinical results of reoperations. The present observations deal with 121 cases: grade 1 astrocytomas (45), oligodendrogliomas (12), grade 2 astrocytomas (47), and oligodendrogliomas (17), respectively. In all these a second reoperation was performed in 14 cases. Operative mortality was relatively high, but without significant difference in the two groups of maligancy: 24.5% and 29.6%. Survival times in both groups showed striking individual differences. We achieved post-reoperation survivals exceeding one year in 18 and 14 cases, respectively. The results of second reoperations were generally poor. We find no remarkable differences in survival time following reoperations in primary grade 1 and grade 2 tumours. Similarly, malignant change proved to be not decisive for survival times. On the contrary, most of our patients with unchanged grade 1 astrocytomas, reoperated on after a longer interval, achieved a short second survival only. Prolongation of life expectancy by radiotherapy is doubtful. Irradiation seems to be necessary with malignantly transformed tumours if the patient did not have any treatment before reoperation.