Squamous cell carcinoma presenting as an orbital cyst with radiologic evidence of perineural invasion

Abstract

<h4>Purpose</h4>To report clinical and radiologic findings of cystic squamous cell carcinoma (SCC) of the orbit with evidence of perineural involvement.<h4>Methods</h4>Analysis of clinical findings and radiology with a literature review.<h4>Results</h4>A 66-year-old man with SCC of the forehead 8 years prior presented with paraesthesias, diplopia, and proptosis. Magnetic resonance imaging showed a well-defined, cystic mass of the orbit with a single, linear structure running through its center. Lateral orbitotomy revealed a cyst adherent to adjacent periorbita containing viscous, clear, yellow substance and a nerve coursing through the center. Histopathology confirmed poorly differentiated spindle cell carcinoma with positive staining for cytokeratin markers, consistent with SCC.<h4>Conclusions</h4>Orbital cysts associated with altered sensation are suggestive of SCC with perineural spread, requiring prompt investigation and treatment to minimize morbidity and mortality. The involved nerve may be seen as a single, linear structure within the mass on imaging.