Endolymphatic sac tumours: surgical management

Area of Science:

• Otolaryngology
• Neurosurgery
• Oncology

Background:

• Endolymphatic sac tumors (ELSTs) are rare, recognized as a distinct entity since 1984.
• ELSTs can be sporadic or associated with von Hippel-Lindau (VHL) disease, confirmed by VHL gene analysis.
• Currently, no standardized diagnostic or treatment strategy exists for ELSTs.

Purpose of the Study:

• To develop and evaluate a novel staging system for endolymphatic sac tumors (ELSTs).
• To correlate tumor stage with surgical approach and patient outcomes.
• To establish a basis for a tailored surgical strategy for ELST management.

Main Methods:

• A staging system was developed based on computed tomography, MRI, and MRA findings in seven consecutive patients.
• Tumors were classified into Type A (local), Type B (bone infiltration), and Type C (sinus/jugular bulb invasion).
• Surgical approaches were adapted to the tumor stage, including various transpetrosal procedures.

Main Results:

• Complete tumor removal was achieved in all seven patients.
• Facial nerve function was preserved in all stages; vestibulocochlear nerve preservation was limited to Type A tumors.
• Postoperative MRI confirmed no local recurrence during a 4-38 month follow-up period.

Conclusions:

• A stage-based surgical strategy facilitates complete endolymphatic sac tumor (ELST) resection with low morbidity.
• Transmastoid approaches are effective for resecting the tumor matrix and preventing local recurrence.
• Tailored surgical management based on a staging system improves outcomes for ELST patients.