Conjunctival Merkel cell carcinoma: case report and review of the literature.

Merkel cell carcinoma (MCC) of the conjunctiva is rare. We report the case of a 73-year-old man who presented with unilateral foreign body sensation and blurred vision. A rapidly enlarging conjunctival lesion was identified and excised. The histopathological diagnosis was poorly differentiated squamous cell carcinoma, later reclassified as neuroendocrine / Merkel cell carcinoma following excision on subsequent recurrence. The patient developed lymph node and widespread metastatic disease. The challenges of diagnosing MCC at this site are discussed and the literature on treatment options for this aggressive disease is reviewed.