Surgical Treatment of an Endolymphatic Sac Tumor

Summary

Here, we discuss clinical and radiological features of endolymphatic sac tumors and report the methodology and results of a surgical removal in a case in care at our otologic referral center.

Abstract

Endolymphatic sac tumors (ELST) are low-grade papillary adenocarcinoma originating from the endolymphatic sac. Usually slow-growing, with local aggressiveness and a low risk of distant metastases, ELST can be sporadic but also frequently associated with von Hippel Lindau disease. The current treatment of ELST is primarily surgical resection. A 55-year-old woman accessed our otologic tertiary level referral center for a sudden worsening of hearing loss in her left ear and vertigo. A magnetic resonance (MRI) and computer tomography scan study subsequently showed a mass in the petrous bone; hence, the presence of an ELST was hypothesized. After embolization of the mass, the patient underwent surgical removal of the lesion. The resection of the mass was done through a translabirinthine approach, with an uneventful procedure. No residual disease remained after surgery. After 24 months of radiologic follow up with MRI, there are no signs of recurrence disease. This paper reports the management of this sporadic ELST, as well as the follow up results, providing clinicians this protocol for the handling of such a challenging otologic skull base surgery and rare disease.

Introduction

Endolymphatic sac tumors (ELST) are neoplasms originating from the endolymphatic sac, a neuroectoderm-derived organ located in the posteromedial surface of the temporal bone. Histologically, ELST are characterizable as low-grade papillary adenocarcinoma¹. Usually, ELST are slow-growing, with local aggressiveness and a low risk of distant metastases^2,3,4. ELST can be sporadic, but they are also frequently associated with von Hippel Lindau disease (VHL)⁴.

Given the slow growing rate, the paucity of the ....

Protocol

The local ethical committee approved the publication of this clinical case. A written informed consent form was collected from the patient.

1. Clinical and audiological evaluation

1. Collect personal or familiar history of VHL disease or compatible symptoms from the patient.
2. Perform a neurological examination to investigate central causes. Ensure that there is no pathological cause to be underlined and the facial nerve function is normal.
3. Assess ex.......

Discussion

ELST are rare and locally aggressive neoplasms that arise on the posteromedial surface of the temporal bone. Due to their slow growth rate, and the initial paucity of the symptoms, the diagnosis is often delayed, resulting in an advanced tumor stage. Since the surgery morbidity as well as the oncologic outcomes are strongly correlated with the tumor dimensions and extension^6,8,13,15, an early d.......

Materials

Name	Company	Catalog Number	Comments
AC40	Interacoustic		Clinical audiometer
AT235	Interacoustic		Clinical tympanometry
Innova 3131	GE Healthcare		Biplane angiograph
LightSpeed VCT	GE Healthcare		64 Slice CT system
S2 πDrive	Striker		Drilling system for Otosurgery
Signa HDX	GE Healthcare		1.5 T MRI system
SYNAPSYS VNG	Inventis		Video nystagmograph