Endoscopic submucosal dissection of an anal canal condyloma with a high-grade squamous intraepithelial lesion.

A 40-year-old woman underwent colonoscopy and a whitish lesion detected at anal canal at local hospital, the histology of biopsy showed squamous cell high-grade dysplasia. The patient was transferred to our center for treatment because of concerning invasive disease. The test for human immunodeficiency virus was negative. Colonoscopy showed an isolated whitish, slightly elevated lesion with estimated size of 10 × 4 mm on anal canal.