Foreign body granulomas simulating recurrent tumors in patients following colorectal surgery for carcinoma: a report of two cases.

We report here two cases of foreign body granulomas that arose from the pelvic wall and liver, respectively, and simulated recurrent colorectal carcinomas in patients with a history of surgery. On contrast-enhanced CT and MR images, a pelvic wall mass appeared as a well-enhancing mass that had invaded the distal ureter, resulting in the development of hydronephrosis. In addition, a liver mass had a hypointense rim that corresponded to the fibrous wall on a T2-weighted MR image, and showed persistent peripheral enhancement that corresponded to the granulation tissues and fibrous wall on dynamic MR images. These lesions also displayed very intense homogeneous FDG uptake on PET/CT.