Pyrexia of unknown origin as the only manifestation of colorectal carcinoma.

Patients with colon cancer rarely present with pyrexia of unknown origin (PUO) without other manifestations or symptoms. The present paper reports a patient who presented with a 6-month history of fever. The patient was found to suffer from well-differentiated adenocarcinoma of the sigmoid colon. A few days after sigmoidectomy the fever subsided and the patient recovered. Investigation of the large bowel should always form part of the evaluation in patients with pyrexia of unknown origin.