Clinical response to pazopanib in a patient with endolymphatic sac tumor not associated with von Hippel-Lindau syndrome

Endolymphatic sac tumors (ELSTs) are rare, locally invasive, vascular tumors of the temporal bone. These lesions are associated with von Hippel-Lindau syndrome but may arise sporadically. Early surgical intervention is recommended to prevent permanent neurologic deficits; however, many ELSTs are unresectable or are subtotally resected due to neurovascular compromise. Chemotherapeutic salvage therapy in trials of neoplasms of associated syndromes has targeted angiogenesis with variable response. We present the case of a sporadic ELST, previously minimally responsive to bevacizumab, treated with pazopanib, a multi-kinase inhibitor and antiangiogenic, with good response. Cases such as our patient may demonstrate the utility of novel antiangiogenics in the treatment of these rare neoplasms, particularly when the tumor is unresectable or necessitates subtotal resection.