Endolymphatic sac tumour, adenoma of the endolymphatic sac, aggressive papillary tumour of the temporal bone / middle ear, low grade adenocarcinoma of endolymphatic origin, Heffner tumour

Epidemiology

This is an extremely rare tumour.

Clinical features

This tumour occurs across a wide age range in adults6. Most cases are sporadic. Others are associated with von Hippel-Lindau syndrome2: about 11% of patients with VHL syndrome develop an endolymphatic sac tumour1. (Both sporadic5 and VHL-associated tumours show inactivation of the VHL tumour suppressor gene4.) Patients commonly have a ten year history of hearing loss before the tumour becomes apparent3.

Radiology

There is a lytic lesion in the posterior wall of the temporal bone6. The tumour often shows calcification.

Histopathology

This is a glandular neoplasm with a papillary-cystic architecture. Cellularity is variable. Low cuboidal cells line papillae and cysts. Deep to these, there is a second row of cells, lacking epithelial markers. Colloid-like material within cystic spaces resembles a thyroid carcinoma.

Immunohistochemistry

	Cytokeratins	positive
	EMA	variable
	S-100	variable
	Vimentin	variable
	GFAP	variable
	NSE	variable
	Chromogranin	negative
	Synaptophysin	negative
	Thyroglobulin	negative
	Transthyretin	negative

Ultrastructure

There are intercellular tight junctions, microvilli, intracytoplasmic glycogen and secretory granules.

Differential diagnosis

Middle ear adenoma: lacks a papillary architecture, positive for chromogranin and synaptophysin.
Ceruminal gland tumour
Choroid plexus tumour: does not destroy bone.
paraganglioma: lacks a papillary architecture, positive for chromogranin and synaptophysin.
metastatic thyroid carcinoma: positive for thyroglobulin and TTF-1.
metastatic renal cell carcinoma: also positive for both cytokeratins and vimentin.

Prognosis

This is a slow-growing tumour. Large tumours are prone to recurrence, but metastases do not occur.

References

1Perez-Ordonex B. Special tumours of the head and neck. Current Diagnostic Pathology 2003;9:366-383.

2Manski, T. J., D. K. Heffner, et al. (1997). "Endolymphatic sac tumors. A source of morbid hearing loss in von Hippel-Lindau disease." Jama 277(18): 1461-6.

3Megerian, C. A., M. J. McKenna, et al. (1995). "Endolymphatic sac tumors: histopathologic confirmation, clinical characterization, and implication in von Hippel-Lindau disease." Laryngoscope 105(8 Pt 1): 801-8.

4Vortmeyer, A. O., S. C. Huang, et al. (2000). "Somatic von Hippel-Lindau gene mutations detected in sporadic endolymphatic sac tumors." Cancer Res 60(21): 5963-5.

5Hamazaki, S., M. Yoshida, et al. (2001). "Mutation of von Hippel-Lindau tumor suppressor gene in a sporadic endolymphatic sac tumor." Hum Pathol 32(11): 1272-6.

6Heffner, D. K. (1989). "Low-grade adenocarcinoma of probable endolymphatic sac origin A clinicopathologic study of 20 cases." Cancer 64(11): 2292-302.

7Kempermann, G., H. P. Neumann, et al. (1998). "Endolymphatic sac tumours." Histopathology 33(1): 2-10.

8Gaffey, M. J., S. E. Mills, et al. (1988). "Aggressive papillary middle-ear tumor. A clinicopathologic entity distinct from middle-ear adenoma." Am J Surg Pathol 12(10): 790-7.

This page last revised 23.2.2004.