Robotic Partial Nephrectomy Feasible for Larger Kidney Tumors
No greater risks for upstaging or positive surgical margins were observed among patients who underwent RPN for cT2a tumors over the short term.
Robotic partial nephrectomy (RPN) is a safe and effective option for some patients with clinical stage T2a kidney cancer, according to a new study.
“RPN for T2a tumors is a feasible treatment option in a select patient population when performed by experienced surgeons in institutions equipped to manage postoperative complications,” Joan C. Delto, MD, of Beth Israel Deaconess Medical Center in Boston, and colleagues concluded in a paper published online ahead of print in BJU International.
In a retrospective analysis, the team compared perioperative and postoperative outcomes with RPN for cT2a tumors (7 to less than 10 cm) and cT1 tumors. Of 1778 patients undergoing RPN at 6 institutions during 2006-2016, 1358 had cT1a, 379 cT1b, and 41 cT2a renal masses. The median size of cT1a, cT1b, and cT2a tumors were 2.5 cm, 5.0 cm, and 8.0 cm, respectively, with modified R.E.N.A.L. Nephrometry scores of 6.0, 6.5, and 7.0, respectively, excluding the radius component.
RPN for cT2a masses was associated with 12% longer operative time, 32% greater estimated blood loss, 7% longer ischemia time, and 4-fold greater risk for acute kidney injury risk at discharge compared with RPN for cT1a tumors. In addition, RPN for cT2a masses was associated with 12% more blood loss and 5% longer operative time compared with RPN for cT1b tumors.
The investigators found no greater risks for complications, positive margins, length of stay, or renal function decline for up to 24 months after RPN for cT2a. However, 42% of cT2a masses turned out to be benign at pathology. Just 4.5% of cT2a tumors were upstaged, compared with 16.8% of cT1 tumors. Results were all significant and were adjusted for operating surgeon and modified R.E.N.A.L. Nephrometry score.
Lower relative risk for recurrence-free survival at 12 months was found with RPN for cT2a compared with cT1a and cT1b (91.7% vs 99.6% vs 100%). “Thus, careful patient selection is indicated for RPN for T2a lesions, and additional studies should further classify who would benefit from partial versus radical surgery. Future multi-institutional investigations should also evaluate outcomes of robotic radical and partial nephrectomy for T2a, high complexity tumors,” Dr Delto and her peers stated.
Given the study's observational design, small number of cT2a cases, possible selection bias, short follow up, and incomplete data (e.g., preoperative biopsy, conversion rate, local vs distant metastases, etc.), randomized trials of RPN for cT2a are needed.
Delto JC, Paulucci D, Helbig MW, et al. Robotic partial nephrectomy for large renal masses: A multi-institutional series. BJU Intl. doi: 10.1111/bju.14139 [Published online]