Cerebellar astrocytomas in childhood.

According to CT appearance and surgical observations, cerebellar astrocytomas can be separated into three types. On CT scan, cystic astrocytomas have a typical mural nodule; with contrast injection only the nodule becomes hyperdense; the wall of the cyst is not modified. In these cases, only the mural nodule is removed since the wall does not contain tumor cells. In contrast, false cystic astrocytomas present an irregular wall, diffusely enhanced and thick. Then the wall is invaded by tumor cells, it must be totally removed. Solid astrocytomas may invade the peduncle, the IV ventricle, and the subarachnoid spaces. Removal is sometimes questionably total. As recurrences are not frequently observed in these cases, radiotherapy is not always recommended. Rather, radiotherapy is only used in cases of undoubted partial removal or after partial removal of a recurrence. Of 63 cases, early postoperative mortality was 4.7% and late recurrence 6.3%.