Not Your Ordinary Hemorrhoid

Abstract

Squamous papillomas are more commonly found in the oral cavity, oropharynx, and esophagus. Here we present a case of a squamous papilloma arising off of an internal hemorrhoid, a rare lesion found in the rectum. A 58-year-old male with a history of nephrolithiasis and chronic constipation, without any prior history of colonoscopy, presented with a chief complaint of LLQ abdominal pain and constipation of 6 weeks duration. He reported straining and use of laxatives prior to defecation. Of note, the patient denied recent illnesses, bloody stools, weight loss or nocturnal symptoms. Perianal and digital rectal exam revealed a firm palpable mass in the rectum. Colonoscopy was performed in which the cecum, ascending, transverse, descending, and sigmoid colon were all visualized as normal. Upon retroflexion of the scope in the distal rectum, a firm nodular mass was appreciated arising from an internal hemorrhoid above the dentate line. Multiple firm biopsies were taken, with the colonoscope in both a retrograde and antegrade fashion. Due to the location and size of the lesion, he underwent a rectal ultrasound which noted a single pedunculated 3 cm polyp on a stalk overlying an internal hemorrhoid. Initially thought to be an anorectal malignancy, histopathological examination revealed small superficial fragments of squamous epithelium that were suggestive of squamous papilloma. No signs of malignancy or dysplasia were noted. HPV related disease was ruled out through the use of P16 Immunohistochemical staining. Squamous papillomas of the rectum are rare and benign lesions that may be mistaken for anorectal malignancy. The tumor is characterized by papillomatous processes and covered by keratinized squamous epithelium. Although uncommon, HPV negative lesions occur and are commonly referred to as “burned-out” condylomas. Colonoscopic retroflexion increases the detection of polyps that may be embedded behind a colonic fold or amidst internal hemorrhoids above the anus. Atypical lesions in the anorectal canal with features of internal hemorrhoids should be biopsied to avoid missing a malignancy. Colonoscopists should keep these lesions in mind when considering the differential diagnosis of an anorectal polyp. The differential diagnosis includes HPV associated squamous cell carcinomas and adenocarcinomas, which are two more common neoplasms of the anorectal canal.2936_A Figure 1. 3 cm polyp visualized in the rectum on colonoscopy.2936_B Figure 2. Endoscopic ultrasound (EUS) consistent with intact submucosa and muscularis propria and no lymphadenopathy.