The authors report the cases of 9 patients whose neurological symptoms were limited to the areas innervated by the cranial nerves, which were affected in a multiple way and, in almost all of the cases, unilaterally. There were neither signs of increased intracranial pressure nor of neurological involvement of other areas not innervated by the cranial nerves. Severe roentgenological alterations of the skull basis, specially located in the middle cranial fossa, were evidenced in 7 cases. Four cases fit the Garcin's syndrome, for the paralysis involved all of the cranial nerves in one side; in the other cases there were associated paralysis of several nerves, generally those of the middle cranial fossa. In view of the clinical picture the diagnosis of tumor of the skull basis could be made, and in 4 of the cases the nasopharyngeal origin of the neoplasm was verified. As to the nature of the tumor, histopathological studies showed that 5 were epitheliomas, 3 were sarcomas, and 1 was a glomus tumor. The authors also report a case in which the symptoms were restricted to multiple paralysis of cranial nerves, the differential diagnosis between tumor of the skull basis and neoplasm of the brain stem being particularly discussed; the post mortem study confirmed the last hypothesis, showing a mycotic granuloma of the pons. In connection with the cases reported, the authors make a review of the subject, considering the history, nature, symptoms, diagnosis, differential diagnosis, treatment and prognosis of the tumoral conditions of the skull basis.