Squamous cell carcinoma arising in a villous adenoma in the colon: a rare but real threat

Abstract

Squamous cell carcinoma (SCC) of the colon is rare, with fewer than 100 cases, predominantly in males, usually presenting at advanced stages with poor prognosis. SCC arising in a villous adenoma of the colon is still rarer. The first case of primary SCC of the colon arising in a villous adenoma was reported by Lundquest et al. Metastasis from other sites like the lungs must be excluded before considering such a case as primary. Here a 54-year-old female presented with a three-month history of epigastric pain and altered bowel habits. A colonoscopy identified an ulcero-proliferative lesion in the ascending colon, which CT imaging confirmed as a neoplastic mass. Histopathological examination of colonoscopic biopsy was diagnosed as SCC. The patient subsequently underwent a right hemicolectomy, and a diagnosis of well differentiated SCC arising in a villous adenoma was given. Postoperative recovery was monitored, and the patient was scheduled for follow-up assessments to manage and detect any recurrence. SCC of the colon arising in a villous adenoma is rare, found mainly in the rectosigmoid region but occasionally in other areas, like the ascending colon. Due to its rarity, it is important to rule out secondary causes. Histological confirmation includes using immunohistochemistry such as p40/63, CK-AE1/AE3 and 34BE12 to confirm squamous cel differentiation. Primary SCC of the colon requires prompt surgery due to its aggressiveness. The effectiveness of chemoradiation is unclear, and increased surveillance is needed due to higher recurrence rates.