Clinicopathologic findings in a dog with a retrobulbar meningioma

Abstract

Abstract. An 11-year-old Fox Terrier dog was evaluated for a 10-month history of progressive exophthalmia and visual deficits in the right eye. Ophthalmologic examination revealed severe corneal fibrosis and pigmentation, which obscured examination of the anterior chamber of the right eye. There was decreased retropulsion of the right eye. Neurological examination revealed an absent menace response bilaterally. Pupillary light reflex was normal in the left eye. Due to the corneal pathology, pupillary light reflex was unable to be evaluated in the right eye. A retrobulbar mass with heterogeneous echotexture was identified using ultrasonography. Cytological evaluation of a fine-needle aspirate of the mass disclosed a neoplastic cell population consisting of round to polygonal cells with lightly basophilic to gray cytoplasm and round to ovoid nuclei having a coarse granular chromatin pattern. Magnetic resonance imaging disclosed a right-sided retrobulbar mass that extended through the optic canal and was contiguous with an extra-axial mass in the ventral right rostral and middle cranial fossae. The mass displayed homogenous and strong contrast enhancement. Following exenteration, histological examination of the retrobulbar mass was consistent with meningioma. Immunohistochemically, tumor cells stained positive for vimentin (cytoplasmic) and E-cadherin (membranous), and negative for S100, pancytokeratin, and cytokeratins AE1 and AE3.

Canine ocular neoplasia: a review

“…Optic nerve atrophy and degeneration and retrograde retinal atrophy with loss of ganglion cells are frequent secondary findings. Larger masses may cause bone remodeling . Orbital meningiomas are immunoreactive for vimentin and NSE.…”

“…Some are immunopositive for S100, e‐cadherin, and GFAP. The neoplastic cells are immunonegative for cytokeratin . The prognosis for life is fair to guarded, as local recurrence may occur.…”

“…Larger masses may cause bone remodeling. 2,9,29,[118][119][120][121] Orbital meningiomas are immunoreactive for vimentin and NSE. Some are immunopositive for S100, e-cadherin, and GFAP.…”

Intradural extramedullary granular cell tumour in a cat

“…MRI findings of CNS GCTs in domestic animals are scarce (Higgins et al 2001, Liu et al 2004, Sharkey et al 2004, Klopp & Ridway 2009, Rao et al 2010, Regan et al 2011, Mishra et al 2012, Anwer et al 2013. Based on these reports, pre-contrast T1W hyperintensity seems to be a consistently striking feature of canine CNS GCT.…”

“…Conversely, domestic animals seem to be rarely affected. To date, intracranial GCTs have been described in 16 dogs (Parker et al 1978, Patnaik 1993, Barnhart et al 2001, Higgins et al 2001, Liu et al 2004, Sharkey et al 2004, Klopp & Ridway 2009, Regan et al 2011, Mishra et al 2012, Anwer et al 2013) and one cat (Mandara et al 2006), whereas spinal GCTs have been reported only in two dogs (Montoliu et al 2006, Rao et al 2010.…”