Abstract
Among colorectal carcinomas, squamous cell carcinomas are rare, especially those arising in the colon. Squamous cell carcinoma of the colon has a poorer prognosis than adenocarcinoma of the colon, with minimal response to treatment. We encountered a case of primary squamous cell carcinoma of the sigmoid colon. An 80-year-old woman complaining of anal bleeding was given a diagnosis of a squamous cell carcinoma of the sigmoid colon after a colonoscopy with a biopsy. General exploration revealed no evidence of another malignancy, and she had no previous history of malignancy. The preoperative diagnosis was primary squamous cell carcinoma of the sigmoid colon. We performed a sigmoidectomy with partial intestine resection due to direct invasion of the small intestine, and we constructed an artificial anus. The center of the tumor was necrotic, forming a cavity. The histopathological findings showed squamous cell carcinoma with slight keratinization. No adenocarcinoma component was detected. The patient died of local recurrence 15 months postoperatively.
