Retroperitoneal abscess: a presentation of colon carcinoma.

Retroperitoneal abscess as an initial manifestation of carcinoma of the colon is unusual. Inappropriate management of an unrecognized lesion is invariably fatal. Awareness of this uncommon presentation can lead to a precise preoperative diagnosis and appropriate therapy. The possibility of a perforated colon carcinoma should be considered in instances of unexplained retroperitoneal mass and infection, and a barium enema performed on all such patients. The authors report 3 cases and illustrate the radiological features of retroperitoneal abscesses due to perforated colon carcinoma.