Abstract
Paragangliomas are rare neuroendocrine tumors originating from extra-adrenal chromaffin cells and often require surgical management. We report the case of a 55-year-old male with a retroperitoneal paraganglioma diagnosed by imaging and elevated catecholamine metabolite levels. Preoperative management included alpha-blocker administration to control blood pressure. The tumor was located behind the inferior vena cava and the left renal vein, necessitating careful surgical planning. During surgery, the left renal vein was temporarily clamped and transected for tumor excision, followed by vascular reconstruction. Periodic declamping was performed to mitigate renal congestion. Postoperatively, the biochemical markers of catecholamine secretion normalized, and renal function remained stable. The patient was discharged without complications. This case underscores the importance of preoperative planning, intraoperative vascular management, and postoperative monitoring in the surgical treatment of functional retroperitoneal paragangliomas. It also demonstrates the feasibility of left renal vein transection and reconstruction for complete tumor resection while preserving renal function.