CASE REPORT Endolymphatic sac tumors: experience of three cases Pierre-Louis Bastier • Erwan de Mones • Magali Marro • Wael Elkhatib • Vale ´rie Franco-Vidal • Dominique Liguoro • Vincent Darrouzet Received: 4 August 2012 / Accepted: 21 November 2012 / Published online: 5 December 2012 Ó Springer-Verlag Berlin Heidelberg 2012 Abstract Objectives To describe the clinical features, radiological findings, treatment and outcomes of three cases of endo- lymphatic sac tumors (ELST). Methods Retrospective analysis of three cases of ELST. Results The first patient had a large ELST invading the labyrinth after a long history of vertigo. He was recurrence- free 1 year after retrolabyrinthine surgical removal. In the second case, an acute peripheral facial nerve paralysis associated with ipsilateral sensorineural hearing loss led to the diagnosis. A translabyrinthine approach was used to remove the tumor, which recurred three times over 10 years. The third patient was a young woman suffering from von Hippel–Lindau (VHL) disease and referred for a sudden sensorineural hearing loss due to an intralabyrin- thine hemorrhage secondary to a 2 mm-large endolym- phatic sac-confined ELST. Her hearing was totally lost after the deafness recurred 1 month after this first episode. MRI demonstrated a small bilateral ELST. The patient refused surgery on the deaf side. Conclusion ELST are difficult to diagnose due to the wide variety of their presentations. Patients with ELST should be screened for VHL disease. Dural invasion and tumor hypervascularization increase the risk of local recurrences after surgery. Early surgical resection may lead to complete tumor removal and inner ear preservation. Keywords Endolymphatic sac tumor Á Von Hippel– Lindau disease Á Intralabyrinthine hemorrhage Á Endolymphatic hydrops Introduction Endolymphatic sac tumors (ELST) were classified by He- ffner in 1989 under the term ‘‘low grade adenocarcinoma of probable endolymphatic sac origin’’ [1]. Other terms have been used such as adenoma of the endolymphatic sac (ELS) and papillary tumor of the temporal bone [2]. These tumors are of neuroectodermal origin and originate from the pars rugosa, the distal intraosseous portion of the endolymphatic sac [3–5]. The term ELST was retained in the WHO head and neck tumor classification in 2005 [6]. ELST are associated with von Hippel–Lindau disease (VHL), a severe autosomal dominantly inherited disease characterized by retinal and central nervous system (CNS) hemangioblastomas, clear cell renal cell carcinoma, pheo- chromocytomas, paragangliomas, pancreatic adenomas and/or cystadenoma of the epididymis or annexes [7–9]. The VHL gene codes for a pVHL tumor suppressor protein that plays a central role in the oxygen-sensing pathway by regulating hypoxia-inducible genes [10]. Inactivation of the VHL gene leads to overexpression of hypoxia-inducible factor targets such as vascular endothelial growth factor or platelet-derived growth factor, which are respectively mitogens for endothelial cells and pericytes [10]. This seems responsible for the hypervascularity of VHL-related tumors. VHL gene mutation has been also found in P.-L. Bastier Á E. de Mones Á M. Marro Á W. Elkhatib Á V. Franco-Vidal Á V. Darrouzet Otolaryngology and Skull Base Surgery Department, University Bordeaux Segalen, 33000 Bordeaux, France P.-L. Bastier (&) Service ORL, Ho ˆpital Pellegrin, Place Ame ´lie Raba-Le ´on, 33076 Bordeaux Cedex, France e-mail: plbastier@orange.fr D. Liguoro Department of Neurosurgery, University Bordeaux Segalen, 33000 Bordeaux, France 123 Eur Arch Otorhinolaryngol (2013) 270:1551–1557 DOI 10.1007/s00405-012-2298-7