Endolymphatic sac tumor: a case report and review of the literature.
BACKGROUND
Papillary tumors of the temporal bone are very rare but aggressive neoplasms. In the past, a middle-ear origin was presumed. Only recently convincing evidence exists that these tumors in fact arise from the endolymphatic sac.


METHODS
We present a case of an endolymphatic sac tumor (ELST) with detailed clinical, imaging, operative, and pathologic data. The literature on this rare tumor type is reviewed.


RESULTS
This 63-year-old woman had a progressive mass lesion in the temporal bone for a period of more than 35 years, resulting in unilateral fifth to eleventh cranial nerve palsy, progressive ataxia, and a pyramidal and pseudobulbar syndrome. Computerized tomography (CT) and magnetic resonance imaging (MRI) showed a tumor invading the pars squamosa and petrosa of the temporal bone, and extending into the middle and posterior fossa. Angiography demonstrated a hypervascular tumor mass. The patient underwent surgery, with nonradical removal of a tumor. Histologic examination demonstrated a papillary ELST. A search through the literature revealed 36 patients with ELST, based on convincing anatomic and histologic considerations.


CONCLUSIONS
It is important to make a distinction between ELST and the more benign middle-ear adenomas, since this leads to a different treatment and prognosis. ELST frequently invades the surrounding structures and extends intracranially. The treatment of choice is a radical resection, although complete resection is impossible in most of the cases. The value of adjunctive radiation therapy remains controversial.
Reijneveld
J
J
Department of Neurosurgery, University Hospital Utrecht, The Netherlands.
Hanlo
P
P
Groenewoud
G
G
Jansen
G
G
van Overbeeke
K
K
Tulleken
C
C
D000236:Adenoma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002343:Carotid Artery, Internal; D002533:Cerebral Angiography; D003397:Craniopharyngioma / Q000473:pathology / Q000601:surgery; D004428:Ear Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D004712:Endolymphatic Sac / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D012888:Skull Neoplasms / Q000473:pathology / Q000601:surgery; D013701:Temporal Bone / Q000473:pathology; D014057:Tomography, X-Ray Computed