Renal venous hemangioma: Report of a rare case.

Renal hemangiomas are typically asymptomatic and considered benign lesions. Arterial hemangiomas are common; however, venous hemangiomas are extremely rare and frequently found incidentally during imaging examinations, which can result in misdiagnosis. The present study reported the case of a 37-year-old man with renal vein hemangioma, initially diagnosed as a left retroperitoneal space-occupying lesion on computed tomography (CT). The patient complained of frequent urination for 1 week, urgency for 1 week and hematuria for 1 day. Renal CT revealed a 3-cm space-occupying lesion in the left retroperitoneum. Subsequently, surgical resection was performed and the venous hemangioma was identified as a left renal vein aneurysm. Due to the rarity of venous hemangioma and the lack of standardized imaging criteria, it is frequently misdiagnosed, making its preoperative diagnosis challenging. The present study summarized and reported this rare case to serve as a reference for clinical physicians.