Endolymphatic Sac Tumor (ELST)
- ELST are rare, slow-growing papillary cystadenomas or low-grade adenocarcinomas.
- Symptoms: sensorineural hearing loss, tinnitus, vertigo, and facial nerve palsy.
- Typically unilateral, can be bilateral in Von-Hippel Lindau syndrome.
- Key Diagnostic Features: CT: permeative retrolabyrinthine bony destruction. Intratumoral calcifications can be seen and are described as "bone sequestra." Sometimes, the lesion may demonstrate bony spicules with a thin shell of reactive bone. MRI may demonstrate intralesional hemorrhage. Intense enhancement with vascular flow voids can be seen.
- DDx: Paraganglioma, vascular metastases, meningioma
- Rx: Surgical
