Condyloma acuminatum of the anal canal, treated with endoscopic submucosal dissection.

Condyloma acuminatum (CA) is a common sexually transmitted disease caused by human papilloma virus infection. Not all individuals develop persistent, progressive disease, but careful follow up is required with moderate-to-severe dysplasia to prevent progression to malignancy. Standard therapies include surgical treatments (trans-anal resection and trans-anal endoscopic microsurgery) and immunotherapeutic and topical methods (topical imiquimod); however, local recurrence remains a considerable problem. Here, we report a case with superficial CA of the anal canal, treated with endoscopic submucosal dissection (ESD). A 28-year-old man presented with a chief complaint of hematochezia. Digital exam did not detect a tumor. Screening colonoscopy revealed 10-mm long, whitish condyles extending from the anal canal to the lower rectum. The lesion covered almost the whole circumference, and only a small amount of normal mucosa remained. Magnifying endoscopy with narrow band imaging showed brownish hairpin-shaped, coiled capillaries. Although histopathological diagnosis by biopsy revealed CA, accurate histological differentiation between CA, papilloma, and squamous cell carcinoma can be difficult with a small specimen. Therefore, we performed diagnostic ESD, which provides a complete specimen for precise histopathological evaluation. The pathological diagnosis was CA, with moderate dysplasia (anal intraepithelial neoplasia 2). There was no recurrence at 16 mo after the initial ESD. Compared to surgical treatment, endoscopic diagnosis and resection could be performed simultaneously and the tumor margin observed clearly with a magnifying chromocolonoscopy, resulting in less recurrence. These findings suggest that endoscopic resection may be an alternative method for CA that prevents recurrence.