Off-clamp Retroperitoneal Laparoscopic Partial Nephrectomy For T₁N₀M₀ Renal Mass And Application Of R.E.N.A.L Score

Objective:To investigate the effect and feasibility of Off-clamp retroperitoneal laparoscopic partial nephrectomy(RLPN)for T1N0M0 renal tumor under the guidance of R.E.N.A.L score.Method:Retrospective comparative analysis of the clinical data of 63 cases of patients with T1N0M0 renal tumor(R.E.N.A.L score ?6)were performed.All procedures were done by the same surgeon in our department from March 2013 to September 2015,including 27 cases with the off-clamp technique and 36 with on-clamp technique.Results:All operations were done successfully with no conversion.The warm ischemia time is 21.6 ±5.3min in on-clamp group,of which the mean intraoperative blood loss and tumor resection time were significantly less than those of off-clamp group(46.2±12.5/113.6±26.3ml,4.3±1.2/5.3±3.2min,p<0.05).However,there were no differences between the two groups in term of operation time,positive surgical margins,postoperative complications rates and postoperative hospital stay(P > 0.05).Although the renal function recovers more evenly and fast in off-clamp group,(postoperative seven-days GFR :62.1±8.3 vs.46.8±9.1ml/min/1.732,P < 0.05;postoperative six-months GFR 72.5±5.7 vs.59.5±7.8 ml/min/1.732,P < 0.05),the eGFR after one year postoperatively were similar between the two groups(76.5±7.9 vs.68.8±9.7 ml/min/1.732,P > 0.05).Furthermore,the average change rate of eGFR in off-clamp groups was less than that in on-clamp group(-2.3/-7.6,p<0.05).All patients were followed up for 12 months with no tumor recurrence and metastasis.Conclusion:1?Off-clamp RLPN has similar effect with on-clamp RLPN according to the postoperative hospital stay,complications,positive margins,rate of intraoperative blood transfusion and long-term renal function recovery.But the short-term renal function recovery is better in the off-clamp.2?R.E.N.A.L score is helpful in estimating the complexity and difficulty of the RLPN pre-operatively.3?Off-clamp RLPN is safe and feasible for T1N0M0 renal tumor with low-grade R.E.N.A.L score(less than 6).