RESUMO
Sporadic endolymphatic sac tumor is a very rare neoplasm. It is low malignant, locally destructive and expansive, but non-metastasizing. The tumor is very rare in the sporadic form, but more often associated with Von Hippel-Lindau disease. A 65-year old man with left sided tinnitus and hearing loss for several months. Audiometry showed an asymmetrical sensory neural hearing loss on the left side up to 60 dB. The speech discrimination score was 46% and stapedial reflexes were absent. Several years earlier, he had suffered from periods of dizziness. Magnetic resonance imaging (MRI) showed a destructive and locally invasive tumor in the peripheral vestibular system expanding into the cerebellopontine angle. Paraganglioma and von Hippel-Lindau`s disease were excluded. Vestibular examination showed no function of vestibular organ left side. The tumor was resected radically by translabyrintine approach. Per-operative freeze-microscopy showed inflammation tissue, whereas subsequent microscopy showed papillary-cystic endolymphatic sac tumor. Endolymphatic sac tumor is a rare neoplasm. The tumor may present with asymmetrically sensory neural hearing loss with or without tinnitus, dizziness and facial nerve paresis. An MRI scan is the appropriate diagnostic tool final dianosis is made by the post-operative histo-pathology. Dizziness can be the first sign of a tumor in this area.