[A clinical study on postoperative course of cerebellar astrocytoma (author's transl)]

We have made a study on the postoperative course of 20 cases with cerebellar astrocytoma observed and treated in Hokkaido University Hospital from 1957 to 1978. Following conclusions were obtained. (1) Among those 20 patients, 16 were alive at the time of submission. The survival rate was 80% at 5 years respectively and the longest survival period for one of our patients is 19 years postoperatively. (2) Removal of tumor was attemped in all cases and the prognosis was best influenced by the degree of removal. The cases who received a complete extirpation of their tumors resulted in a permanent and complete cure, but the cases of incomplete removal did not give so good results as the cases of complete removal. (3) In the cases who could removed completely, those cases had several factors in common, and from our clinical data, the following factors should be considered. 1. Growth of tumors was circumscribed and tumors did not infiltrate the substance of the brainstem. 2. Tumors arising in the cerebellar hemisphere were found to be more common than those originating in the vermis. 3. It was notable that gross appearance of tumors was high incidence of cystic lesions. 4. Those tumors were a well-differentiated histomorphology and it was found that an overwhelming majority of those astrocytoma were so-called astrocytoma grade I. (4) A particularly benign prognosis was expected when the neoplasm occurred in childhood, but even adult cases if removed completely with several factors mentioned above, demonstrated a good prognosis.