[Progressive cranial neuropathy due to perineural spread of a facial squamous cell carcinoma]

The paper aims to present the case of a progressive and unilateral cranial polyneuropathy due to perineural spread of cutaneous squamous cell carcinoma. This is a case of a 73 year old man with a history of squamous cell carcinoma in the right temporal region that was removed in 1992. In May 2000 he first presented pain and numbness in the distribution of the first branch of right trigeminal nerve and weakness of the ipsilateral frontal muscle. Later on he presented right ophthalmoplegia, and damage of lower cranial nerves, leading to dysphagia and respiratory distress. He was admitted in March 2001 for a gastrostomy for feeding, when ataxia and recurrence of the right temporal lesion ensued. After three examinations with MRI, the fourth study showed meningeal carcinomatous and a metastatic lesion in the brainstem. Histopathologic examination demonstrated dermal and perineural invasion by squamous cell carcinoma. The necropsy also showed meningeal, perineural and endoneural infiltration of atypical epidermal cells and a pons mass composed of the same cells. We conclude that the perineural spread of the cutaneous carcinoma is an exceptional cause of cranial neuropathy, however it must be ruled out in patients with progressive and unilateral cranial neuropathy. In these cases, when no radiological abnormalities are noted, a biopsy may be performed on the peripheral branches of the cranial nerve to confirm the diagnosis.