NEPHRON-SPARING SURGERY IN PATIENTS WITH RENAL CELL CARCINOMA EXTENDING TO THE MAIN RENAL VEIN: INTRARENAL AND EXTRARENAL THROMBECTOMY.

In most cases RCC with venous extension is an indication for radical nephrectomy. However, in patients with imperative indications for nephron-sparing surgery a kidney resection with thrombectomy in rare situations is possible. We present a surgical technique for nephron-sparing surgery in patients with tumor spreading into the main renal vein. From 2007 to 2019 seven partial nephrectomies with removal of the tumor thrombus from the main renal vein were performed. Absolute imperative indications were recorded in 6 (85.7%) patients (4 with solitary kidney, 2 with bilateral tumors). Dimensions of renal tumor averaged 6.5±2.3 cm. Intravenous part of the tumor penetrated the initial portion of the renal vein in 3 cases, main trunk of the renal vein in 3 cases, and cavarenal portion of the IVC in 1 case. The average length of the tumor thrombus was 24.0±6.9 mm, and the width was 9.3±4.8 mm. Tumor thrombi were classified as intrarenal and extrarenal. In accordance with this principle surgical procedures were divided into partial nephrectomy with intrarenal (3/42.9%) and extrarenal thrombectomy (4/57.1%). Intrarenal thrombectomy was characterized by thrombus removal out of the vein lumen from the side of the kidney resection area, while extrarenal thrombectomy included additional opening the lumen of the main renal vein or inferior vena cava (IVC). In one patient hypothermic perfusion of the kidney in situ was used. In two cases the extracorporeal partial nephrectomy with kidney autotransplantation was performed. Warm ischemia time averaged 14.0 minutes. The time of ischemia during hypothermic perfusion in situ reached 76 minutes, the time of cold ischemia during extracorporeal surgery averaged 68.0 minutes. The volume of blood loss did not exceed an average of 621.4±146.8 ml. Early postoperative complications occurred in 4 (57.1%) cases (bleeding -1, ischemic stroke -1, deterioration of renal failure -2). Postoperative mortality was registered in 1 patient due to bleeding and heart failure. The follow-up period averaged 28.7±18.9 months. Distant metastases occurred in 1 (14.3%) patient after 16 months. Local tumor recurrence in the remnant kidney after nephron-sparing surgery was not detected in any case. Nephron-sparing surgery may be used to treat patients with kidney tumors and neoplastic venous thrombosis. However, this complex surgical approach requires further technical improvement.