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.

©SMUHT/PW Bishop