Six cases of supratentorial astrocytomas are presented in this study in order to demonstrate the typical development of this kind of tumors. All patients were controlled regularly by CT scan. Five of them were operated two times, one patient three times. The tumor growth was quite similar in all cases. Time interval between the first intervention and tumor recurrence was larger than between second intervention and tumor recurrence. In all cases the tumors tended to "explosive" growth after the second operation. There are discussed pros and cons of an early reintervention after tumor recurrence.