Use of esophagoscopy in the diagnosis of esophageal squamous cell carcinoma in a horse.

Esophagoscopy allowed visualization and biopsy of a lesion within a diverticulum of the esophagus in an adult horse. Although the biopsy specimen obtained was small, diagnosis of squamous cell carcinoma was possible from histologic examination of the esophageal tissue sample retrieved by use of endoscopy.