Polymorphous low-grade adenocarcinoma with cavernous sinus involvement presenting as third nerve palsy

Abstract

Purpose: Polymorphous low-grade adenocarcinoma is a tumor of the salivary glands that typically localizes within the oral cavity. We present a case of isolated third cranial nerve palsy as the initial presentation of polymorphous low-grade adenocarcinoma involving the left cavernous sinus in a patient status post glaucoma surgery.

Observations: A 68-year-old woman status post glaucoma drainage device implantation in her left eye presented with an isolated left third nerve palsy ten weeks postoperatively. Differential diagnoses included microvascular ischemic neuropathy, postoperative ptosis, and compressive mass. MRI revealed a left cavernous sinus mass, and subsequent excisional biopsy revealed a diagnosis of polymorphous low-grade adenocarcinoma.

Conclusions: There are few cases reporting polymorphous low-grade adenocarcinoma originating from and extending beyond the nasopharynx. This report emphasizes an unexpected neuro-ophthalmic manifestation of this salivary gland tumor.

Keywords: Glaucoma; Neuro-ophthalmology; Polymorphous low-grade adenocarcinoma; Third nerve palsy.

Fig. 1

Humphrey Visual Field 10-2 SITA Standard of the left eye showing advanced glaucoma at a) first presentation to glaucoma clinic and b) most recent clinic encounter.

Fig. 1

Humphrey Visual Field 10-2 SITA Standard of the left eye showing advanced glaucoma at a) first presentation to glaucoma clinic and b) most recent clinic encounter.

Fig. 2

OCT corresponding to earliest visual field testing (Fig. 1a) shows superior and inferior RNFL thinning of the left eye.

Fig. 3

Contrast-enhanced coronal T1 MRI showing a lobulated enhancing lesion in the left cavernous sinus that extends laterally into left sphenoid wing, medially across midline, anteriorly into the left sphenoid sinus and inferiorly into the left nasopharynx (red arrow), eroding the skull base. The mass encases and narrows the petrous segment of the left internal carotid artery and effaces the left foramen ovale and rotundum. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 4

Contrast-enhanced axial T1 MRI. The left cavernous sinus lobulated enhancing lesion extends laterally into left sphenoid wing and medially across midline.

Fig. 5

A: Tubular pattern (H&E, 200x); B: Cribriform pattern (H&E, 200x); C: Solid pattern (H&E, 200x); D: Tumor is positive for CK7 immunostain (10x); E: Tumor is positive for p63 immunostain (10x); F: Tumor is negative for p40 immunostain (10x).