A Vanishing Malignant Appearing Giant Pseudopolyp

Abstract

Introduction Pseudopolyposis is a common finding in ulcerative colitis (UC), though the presence of giant pseudopolyposis (pseudopolyps greater than 1.5 cm in height) is rare and often requires surgical intervention. We present a case of a large, malignant appearing giant pseudopolyp that resolved with medical therapy alone. Case Description A 36 year old Caucasian female with a two year history of UC and primary sclerosing cholangitis (PSC) presented to our clinic for consultation regarding uncontrolled UC symptoms. Her UC was treated previously with mesalamine, prednisone, and adalimumab with little relief in her symptoms. Colonoscopy revealed moderate pancolitis. Her treatment was changed to infliximab and azathioprine with rapid clinical improvement. Colonoscopy was repeated one year after initiation of combination therapy to assess for mucosal healing, and a 3-4 cm ulcerated mass was noted in the cecum emanating from the appendiceal orifice, which was concerning for malignancy (Figure 1). The remaining colon was normal with no evidence of active UC. Histology of the mass showed granulation tissue and crypt architectural irregularity, but no neoplastic tissue. A repeat colonoscopy with biopsies revealed similar findings. A CT scan was concerning for malignancy in the cecum (Figure 2). Despite this concern, the patient decided against surgical intervention. Repeat colonoscopy 8 months later revealed a normal cecum with no sign of a mass (Figure 3).FigureFigureFigureDiscussion Pseudopolyps occur when ulcers penetrate the muscularis mucosa, leaving islands of regenerative tissue, which grow in size with the propulsion of bowel contents. They are by definition non-neoplastic, and have low risk of transforming into neoplasm, however there is a case report of occult dysplasia and adenocarcinoma found within a giant pseudopolyp. Clinically, giant pseudopolyposis is important because there are reports of giant pseudopolyps serving as the nidus for intussusception, and also causing colonic and small bowel obstruction. Because of the concern for malignancy and complications, giant pseudopolyps are often surgically resected. Given our patient's history of PSC which significantly increases the risk of colon cancer as well as the concerning CT scan findings, surgery was advised. Interestingly our patient's giant pseudopolyp resolved with time. It is plausible therefore that with prolonged medical therapy, giant pseudopolyps may resolve preventing the need for surgery.