Researchers have shown that robotic partial nephrectomy is safe and effective for renal masses larger than 4 cm.
"The laparoscopic partial nephrectomy is a technically challenging operation, and for those with T1b tumors, it may be particularly challenging," said senior author Craig G. Rogers, MD, director of robotic renal surgery at the Vattikuti Urology Institute of Henry Ford Hospital, Detroit. "Robotics may help expand the indications of partial nephrectomy, allowing more patients to achieve the convalescence benefits of a minimally invasive partial nephrectomy, even those with larger tumors."
In the first report to examine the utility of robotic partial nephrectomy for larger masses, Dr. Rogers presented his experience with the technique for renal masses larger than 4 cm at the 2009 World Congress of Endourology.
The length of hospital stay and complication rates were similar between the two groups. There were no positive surgical margins in any of the 12 patients with T1b masses.
Low warm ischemia time
Although the mean warm ischemia time was higher in the study group, Dr. Rogers pointed out that it was still quite low at less than 30 minutes.
"Even with large tumors, there was a low warm ischemia time," he said.
The increased warm ischemia time is at least partly due to the fact that most patients had a sutured repair of the collecting system. Additionally, over 90% of the patients in the study group underwent hilar clamping of both the renal artery and vein, which was higher than in the smaller mass group. A similar trend of longer warm ischemia time in larger masses was seen in two large case series of T1b renal masses treated by laparoscopic partial nephrectomy by experienced laparoscopic surgeons.
"We were able to achieve comparable results with robotic partial nephrectomy that were at least on par with comparable laparoscopic series of patients with tumors >4 cm performed by surgeons from major centers with extensive laparoscopic experience," Dr. Rogers commented.
Robotic partial nephrectomy is currently undergoing an early phase of validation, as pioneers of the procedure report their experience in an attempt to assess its safety and feasibility for progressively challenging masses. Laparoscopic partial nephrectomy underwent a similar process in the early 2000s, as experienced surgeons expanded its indications and demonstrated comparable oncologic and functional outcomes in comparison to open partial nephrectomy.
The Vattikuti Urology Institute study is continuing a similar process for robotic partial nephrectomy. Its findings suggest that robotic partial nephrectomy is at least equivalent to laparoscopic partial nephrectomy for larger masses.
Dr. Rogers said he is hopeful that the use of robotics will continue to make a minimally invasive partial nephrectomy accessible to more patients, even those with larger tumors.