Squamous cell carcinoma invading the right temporomandibular joint in a Belgian mare

Abstract

This report describes a rare case of squamous cell carcinoma invading the right temporomandibular joint, right guttural pouch, and calvarium. Radiography, computed tomography, and histopathology were performed in the diagnostic workup. Computed tomography depicted more accurately than radiography the invasive nature, exact location, and extent of the lesion.

Figures

Figure 1

A — Lesion-oriented oblique radiograph of the right caudodorsal head demonstrating soft tissue swelling containing amorphous mineralization (arrowhead). B — Lateral radiograph of the caudal head and pharynx. One of the guttural pouches is fluid- and gas-distended, displacing the dorsal pharyngeal wall ventrally (arrow). An additional, smaller gas lucency representing the other guttural pouch is, visible in the dorsal neck area (arrowheads).

Figure 2

A — Transverse computed tomography images of the caudal head showing the right guttural pouch is fluid- and gas-distended (arrowheads), compressing its left counterpart. There is erosion of the right stylohyoid bone, petrous temporal bone, and calvarium (arrows). Notice the right external soft tissue swelling containing small gas bubbles (*). B — Transverse computed tomography images of the caudal head showing marked osteolysis of the right mandibular ramus and condyle as well as mandibular fossa of the temporal bone (arrowheads). There is also irregular periosteal reaction along the medial aspect of the right mandible (arrow).