The Gruppo Otologico experience of endolymphatic sac tumor.

Objective: Endolymphatic sac tumor (ELST) is a rare low grade adenocarcinoma of the skull base. During the past decade the number of the reported cases has increased. This study exposes our experience in the management of ELST with a review of the literature.

Study Design: Retrospective study of patients with ELST at a quaternary referral otology and skull base center.

Methods: A review of the records from the Gruppo Otologico revealed 7 patients treated for ELST. All papers containing series of three or more cases of ELST published in the English literature were selected for analysis.

Results: Hearing loss and tinnitus were present in almost all our cases. All of them were evaluated with audiometric tests, computed tomography and magnetic resonance imaging. All the patients were treated surgically with preservation of the facial nerve and preoperative embolization was performed in 5 patients. Genetic study was performed on all our cases and revealed the presence of von Hippel-Lindau syndrome in one patient who had the tumor as the initial manifestation of his syndrome. None of the patients received postoperative radiotherapy and one of them had recurrence of the tumor 13 years following surgery.

Conclusions: Complete surgical resection with preoperative embolization of large tumors is the mainstay treatment for ELST. The facial nerve should not be sacrificed unless it is totally invaded by the tumor. A long term follow up is recommended and the role of postoperative adjunctive radiotherapy is still controversial.