SECONDARY MALIGNANT-TUMORS OF THE VESTIBU LOCOCHLEAR AND FACIAL NERVES

Introduction Neuromas and meningiomas represent by far the most freque nt tumors of the cerebellopontine cistern (respectively over 80% and o vers 10%). Secondary malignant tumors are exceptional. Method Presenta tion of four cases of malignant tumors of the cerebellopontine cistern , either revealing or complicating a primary tumor: a bronchial cancer , a cancer of the kidney, a medulloblastoma and a lymphoma. Patients w ere studied in T2- and T1-weighted high-field MRI sequences before and after gadolinium injection. Results The four tumors were enhanced by gadolinium and shown to invade the internal auditory canal, including one bilateral involvement. In most cases, the tumors were slightly het erogeneous and had irregular margins. Conclusion These observations su ggest that other diagnoses than acoustic neuroma should be taken into account.