Renal anastomosing hemangioma following partial nephrectomy for renal cell carcinoma: A case report.

Background: Renal anastomosing hemangioma (AH) is a rare benign vascular tumor characterized by unique histopathological features.

Case Summary: We report a highly unusual case of renal AH. A male patient had undergone partial nephrectomy for clear cell carcinoma of the kidney four years prior. A follow-up computed tomography scan in the third postoperative year revealed a new mass near the surgical site on the same side of the kidney, raising suspicions of tumor recurrence. However, the characteristics on contrast-enhanced magnetic resonance imaging and ultrasonography were more consistent with those of a benign lesion. The patient strongly insisted on undergoing surgery due to concerns about the possibility of renal cancer recurrence. Postoperative pathology confirmed the diagnosis of renal AH.

Conclusion: This case report presents the imaging features of a patient with rare renal AH and a history of renal clear cell carcinoma, providing broader insights into the differential diagnosis of new lesions after surgery for renal cell carcinoma.