Clinical experience of Mayo 0-IV tumor thrombus treated with radical nephrectomy and inferior vena cava thrombectomy

Objective To investigate the safety and feasibility radical nephrectomy and Mayo 0-Ⅳ venous thrombectomy. Methods The clinical data 52 patients with Mayo 0-Ⅳ tumor thrombus from February 2015 to January 2017 were analyzed retrospectively. Of the 52 patients, 42 were male and 10 were female. The average age was (59.8 ±13.6) years old (2.5 to 84.0 years). The renal vein tumor thrombus or inferior vena cava tumor thrombus was found in all patients, including type 0 thrombus in 12 cases, typeⅠthrombus in 11 cases, type Ⅱthrombus in 15 cases, type Ⅲthrombus in 9 cases, type Ⅳ thrombus in 5 cases (Mayo Medical Center classification). Imaging suggested the right renal tumor in 36 cases and left tumor in 16 cases. The average tumor size was (8.5±2.0) cm(2.0-21.1 cm). There were 2 cases ASA Ⅰ, 40 cases ASA Ⅱ and 10 cases ASA Ⅲ according to the American Society Anesthesiologists (ASA). In laparoscopic radical nephrectomy and Mayo 0 venous thrombectomy, we clamped the vena cava vessel wall nearby the renal vein entrance. The vena cava blood flow was blocked partially. Then we cut the vessel wall arcuately. Mayo Ⅰ tumor thrombus requires the use a non traumatic auricle clamp to control blood flow by the block vena cava above thrombus, vena cava below the renal vein level, and the contralateral renal vein. Right kidney tumors with Mayo Ⅱ could be completed by retroperitoneal surgery. At the time vascular occlusion, the distal inferior vena cava, the left renal vein and the proximal inferior vena cava were interrupted sequentially. For left renal tumors with Mayo Ⅱ, the retroperitoneal approach combined with transperitoneal approach was used. The technique of milking can shrink the tumor thrombus and reduced the difficulty the operation. For Mayo Ⅲ tumor thrombus just at the hepatic vein level, we cut off 3-5 hepatic short veins, and separated inferior vena cava long enough to provide surgical field. For Mayo Ⅲ tumor thrombus much higher than the hepatic vein level, we used open surgeries to free the liver and porta hepatis. We first blocked the distal inferior vena cava, followed by the left renal vein, the hepatic artery and portal vein, at last the proximal inferior vena cava. Mayo Ⅳ tumor thrombus often required a median incision to open the chest and establish an extracorporeal circulation. Results All the 52 surgeries were completed successfully without intraoperative and perioperative mortality. Open radical nephrectomy and inferior vena cava thrombectomy was underwent in 22 cases. Pure laparoscopic surgery was under went in 30 case. Two cases were converted to open surgery. The average surgery time was(333.7±80.1)min(136-694 min). The average blood loss volume was (1339.0±508.1)ml(20-10 000ml). During the operation, the amount suspended red blood cells transfusion was(761.5±394.8)ml(0-10 400ml). 28 cases underwent regional lymph node dissection, and postoperative pathological diagnosis showed lymph metastasis in 4 cases. 24 cases underwent ipsilateral adrenalectomy, and 2 cases showed tumor invasion adrenal gland. 7 cases with right tumors underwent inferior vena cava wall resection because invasion by tumor thrombus. The average postoperative hospitalization all 52 cases was (9.7±4.7) d. Among 27 patients, early postoperative complications occurred in 18 cases (34.6%). There were 1 case Clavien Ⅰ, 12 cases Clavien Ⅱ, 1 case Clavien Ⅲa, 2 cases Clavien Ⅳa and 2 cases Clavien Ⅴ according to modified Clavien classifications.44 cases(84.6%) were followed up for 1 to 22 months with a median 8 months. Postoperative recurrence occurred in 3 cases, and distant metastasis occurred in 9 cases. 9 cases (20.5%) had tumor specific death. Conclusions Our initial clinical results show that radical nephrectomy and inferior vena cava thrombectomy is safe and effective for patients with Mayo 0-Ⅳtumor thrombus, but the wide extension vein tumor thrombus leads to the difficulty operation technique. Sufficient preoperative preparation, rich operative experience and skills can improve the safety operation. Key words: Renal carcinoma; Tumor thrombus; Inferior vena cava