Endolymphatic sac tumours

We present a case of a papillary tumour of the petrous bone. The established terminology for this rare neoplasm is endolymphatic sac tumour (ELST) but the true origin remains controversial. ELSTs are associated with von Hippel-Lindau disease. They are locally invasive, highly vascular and often require endovascular embolization prior to surgery. Both radiologically and histologically ELSTs are easily mistaken for other more common tumours such as paragangliomas and renal or papillary thyroid carcinoma metastases. This is important because local excision is curative.