[Clivus C2 aneurysmal bone cyst--contribution to problems of surgical treatment, radiotherapy and individually determined growth trends].

A man of 46 years of age had recurrences of an aneurysmatic bone cyst (Clivus C1/2) despite of repeated radical operations (3 times, transoral approach). Additional radiotherapy resulted in stabilization and cure. Problems of surgical treatment, radiotherapy and of tendency to growth inherent in the lesion are discussed.