An endolymphatic sac tumor with imaging features of aneurysmal bone cysts: differential diagnostic considerations

Background

Endolymphatic sac tumors (ELSTs) are rare, slow-growing tumors of the petrous bone. Despite the typical localisation, their radiological diagnosis can be challenging due to the variety of other tumors potentially showing similar features.

Case report

We present a 16-year-old child with progressive hearing loss, vertigo, and tinnitus who had a large petrous bone lesion showing imaging features of both ELSTs and aneurysmal bone cysts (ABCs). The patient underwent preoperative embolization of the tumor-supplying vessels and subsequently a subtotal resection. Histological examination revealed an ELST.

Conclusion

Despite the rarity of petrous bone ABCs, they should be considered as a differential diagnostic alternative of ELSTs due to their similar imaging appearance.