[Inflammatory pseudotumor of the urachus. A case].

The occurrence in a 9-year old boy of a painful, prominent and solid mid-hypogastric tumour is reported. This clinically isolated muscular tumour was suggestive of sarcoma. En bloc resection of the tumour including the attached vesical cupula was performed. Histology showed that this large tumour was purely inflammatory and had developed from remnants of the urachus. This diagnosis must be considered whenever a suprapubic tumour is discovered. Since malignant transformation of urachus cysts is possible, surgical resection is advised.