Clinical features and treatment of endolymphatic sac tumor

Abstract

Background: Endolymphatic sac tumor (ELST) is an extremely rare disease that does not have established clinical guidelines.

Objective: To provide guidance for the diagnosis and management of ELSTs.

Methods: We retrospectively reviewed the medical records of patients who were suspected to have a lesion in the location of endolymphatic sac. Seven patients were included. Histopathologic diagnosis confirmed five ELSTs and two other diseases.

Results: All of the enrolled patients had hearing impairment. Facial palsy was found in four out of five patients with ELST, whereas none of the patients in other disease group showed facial palsy. CT and MRI findings were consistent with those in previous literatures; however, angiographic findings were not consistent with those previously reported. All patients underwent surgery. Recurrence occurred in two patients with ELST, although there was no visible remnant tumor after the operation. These patients were treated with stereotactic radiosurgery.

Conclusion: Hearing impairment and facial palsy were representative symptoms of ELST. All ELSTs showed ‘salt and pepper’ signal in MRI T1-weighted images, and smaller tumors could have blood supply from AICA in the radiologic study. Complete surgical resection with optional stereotactic radiosurgery should be considered in ELST.

Highlights

• Hearing impairment and facial weakness are remarkable symptoms of ELST compared to other diseases that invade the endolymphatic sac.

• All ELSTs showed ‘salt and pepper’ signal in MRI T1-weighted images.

• ELST less than 3 cm in diameter could have blood supply from AICA.

• A complete surgical excision with optional stereotactic radiosurgery is required.

Chinese abstract

背景：内淋巴囊肿瘤（ELST）是一种极为罕见的疾病, 尚未建立临床指南。

目的：为ELST的诊断和治疗提供指导。

方法：回顾性分析疑有内淋巴囊部位病变的患者的病历资料。包括7名患者。病理组织学诊断证实了5例ELST和2例其他疾病。

结果：所有入选患者均有听力障碍。5例ELST患者中有4例出现面瘫, 而其他疾病组无1例出现面瘫。CT、MRI表现与文献中的一致, 但血管造影表现与以前报道的不一致。所有病人都接受了手术。2例ELST术后虽然无明显残留肿瘤, 但却有复发。这些病人接受立体定向放射外科治疗。

结论：耳聋、面瘫是ELST的典型症状。所有的ELST在MRI T1加权影像中均显示“盐和胡椒”信号, 根据放射学研究, 较小的肿瘤可由AICA供血。对于ELST, 应考虑全切术和选择性立体定向放射外科手术。

Keywords:

• Endolymphatic Sac
• von Hippel-Lindau disease
• skull base neoplasms
• temporal bone
• facial paralysis

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Conceptualization: MIS, BSH. Data curation: CJY, JJS, KSH. Formal analysis: BSH, KSS. Methodology: MIS. Project administration: BSH. Visualization: KSS, BSH. Writing – original draft: BSH. Writing – review and editing: MIS.