PURPOSE: We evaluated the functional outcome, safety and efficacy of zero 
ischemia laparoscopic radio frequency ablation assisted tumor enucleation 
compared with conventional laparoscopic partial nephrectomy.
MATERIALS AND METHODS: A prospective randomized controlled trial was conducted 
from April 2013 to March 2015 in patients with cT1a renal tumor scheduled for 
laparoscopic nephron sparing surgery. All patients were followed for at least 12 
months. Patients in the laparoscopic radio frequency ablation assisted tumor 
enucleation group underwent tumor enucleation after radio frequency ablation 
without hilar clamping. The primary outcome was the change in glomerular 
filtration rate of the affected kidney by renal scintigraphy at 12 months. 
Secondary outcomes included changes in estimated glomerular filtration rate, 
estimated blood loss, operative time, hospital stay, postoperative complications 
and oncologic outcomes. The Pearson chi-square or Fisher exact, Student t-test 
and Wilcoxon rank sum tests were used.
RESULTS: The trial ultimately enrolled 89 patients, of whom 44 were randomized 
to the laparoscopic radio frequency ablation assisted tumor enucleation group 
and 45 to the laparoscopic partial nephrectomy group. In the laparoscopic 
partial nephrectomy group 1 case was converted to radical nephrectomy. Compared 
with the laparoscopic partial nephrectomy group, patients in the laparoscopic 
radio frequency ablation assisted tumor enucleation group had a smaller decrease 
in glomerular filtration rate of the affected kidney at 3 months (10.2% vs 
20.5%, p=0.001) and 12 months (7.6% vs 16.2%, p=0.002). Patients in the 
laparoscopic radio frequency ablation assisted tumor enucleation group had a 
shorter operative time (p=0.002), lower estimated blood loss (p <0.001) and a 
shorter hospital stay (p=0.029) but similar postoperative complications 
(p=1.000). There were no positive margins or local recurrence in this study.
CONCLUSIONS: Zero ischemia laparoscopic radio frequency ablation assisted tumor 
enucleation enables tumor excision with better renal function preservation 
compared to conventional laparoscopic partial nephrectomy. Less blood loss and a 
shorter operative time were achieved with similar postoperative complication 
rates.