The authors describe an uncommon case of a localized form of idiopathic retroperitoneal fibrosis in a 70-year- old patient. They considered the tumour in the right hypogastrium (20×18×10 cm) malignant. The result of histological examination was surprising – Ormond’s disease. The process could not be removed without damaging the common iliac artery. Simple suture of the artery proved unsuitable. During the postoperative period occlusion of the artery developed which was successfully resolved by an aorto-femoral bypass. Half a year after surgery the patient did not suffer a relapse.

        Key words: localized retroperitoneal fibrosis – diagnosis – treatment