[Carcinoma of the urachus: report of two cases].

Carcinoma of the urachus is a rare disease with poor prognosis. This is probably due to the difficulty of preoperative diagnosis. Radiological modalities have been considered to be of little value, but in many cases, preoperative diagnosis can be established with the aid of CT scan. In patients with urachal carcinoma, CT scan visualize the primary tumor and its extension beyond the bladder wall into the space of Retzius. Although about 150 cases of urachal tumor have been reported in the English literature, computerized tomographic findings have not been established. We present two cases and emphasize the usefulness of CT scan in preoperative diagnosis.