Primary squamous cell carcinoma of the colon is exceedingly rare. We present the case of an 83-year-old man who arrived at the Emergency Department of Laredo Medical Center complaining of abdominal pain. He was found to have signs of bowel obstruction and imaging studies revealed the presence of a 7 cm intraabdominal mass. Colonoscopy confirmed there was an obstructive colonic lesion in the hepatic flexure. Intraoperatively, it was found to have perforated the colon, forming an intraabdominal mass that directly extended into the gallbladder. Histopathologic examination confirmed a malignant neoplasm with morphology and immunophenotype diagnostic for poorly differentiated squamous cell carcinoma. An extensive workup failed to demonstrate squamous cell carcinoma in any other anatomic sites; therefore, it was concluded that it was not metastatic and, corresponded to a primary squamous cell carcinoma of the colon. Given the patient’s age and comorbidities, he experienced a rapid decline in health and expired two days after surgery. We present this case to add to the existing literature and discuss the clinical characteristics, significance and pathogenesis, as well as emerging therapeutic strategies for this rare and aggressive form of colorectal cancer.
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