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).