Laparoscopic Partial Nephrectomy: Rest in Peace

Abstract

Is robotic partial nephrectomy (RPN) a superior operation to laparoscopic partial nephrectomy (LPN)? In the article by Choi et al [1] in this month’s issue of European Urology, a total of 23 studies with 2240 patients were evaluated and revealed that RPN has numerous superior outcomes compared with LPN. RPN was found to provide a better postoperative estimated glomerular filtration rate, a lower conversion (to open or radical surgery) rate, shorter warm ischemia time, and shorter length of stay. Proponents of LPN will argue that these studies are difficult to examine scientifically because of a lack of standard anatomic scoring (PADUA or RENAL score), a lack of randomization, or unrecognized retrospective biases. Such arguments are certainly valid, but are they ultimately meaningful in the modern surgical context? It is true that identical dissections can be performed laparoscopically and robotically; however, the adjunctive ability of a robotic surgeon to sculpt the excision and efficiently suture the defect is far superior to the laparoscopic approach. The robot allows, for example, sliding-clip renorrhaphy, which provides improved operative times, warm ischemia times, and closing tension [2,3]. Laparoscopic suturing is difficult, inelegant, and imprecise. In contrast, robotic suturing is targeted and exact and can become facile after a relatively short learning curve [4]. Is it possible to test this claim in a controlled, standardized study? To do so, especially in human participants, would be extremely difficult, as each kidney and mass is different. However, if one is to view some of the older laparoscopic videos of partial nephrectomy (PN), a straightforward, intuitive conclusion can be drawn. It is clear that the LPN technique seems suboptimal, except in a historical context. It is also true that several expert laparoscopic surgeons have transitioned their practice to robotic surgery. This includes senior minimally invasive surgeons at our institution (including S.B.B.), and a senior author of the present article (Koon Ho Rha) [1]. Certainly, in reviewing the ‘‘household names’’ of laparoscopic surgery, the literature reports very few who are continuing to perform laparoscopic prostatectomy, laparoscopic cystectomy and ileal conduit formation, and/or LPN. It is unlikely that experienced laparoscopic surgeons would switch to the robotic technique if the robot offers no value. Is it possible to evaluate this in a randomized study? At present, it is impossible because experts cannot go back in time and do an equivalent number of robotic and laparoscopic cases for learning curve equalization. Although now it is clear that certain surgical and clinical outcome parameters are better with RPN, the assertion that LPN is a suitable alternative assumes that surgeons would be able to perform LPN. Pragmatically, however, surgeons cannot easily perform LPN. Learning curve data from experts suggest extreme differences. The quoted learning curve for RPN is approximately 25 cases [4], whereas the learning curve for LPN is estimated to be>200 cases [5]. The fact is that LPN simply is not an option in the modern era, with robotic technology ubiquitous at most major centers. There are no longer enough experienced laparoscopic surgeons to perform LPN in high volume and thus train the next generation of urologists. This does not mean that existing LPN experts should transition to RPN, but it suggests that they may not have proteges who can perform the procedure. It has been increasingly accepted that PN is the standard treatment for T1 renal tumors. Accordingly, the most recent iteration of the American Urological Association’s guidelines references advantages of PN and recommends it as first-line therapy. When compared with radical nephrectomy, PN EURO P E AN URO LOGY 6 7 ( 2 0 1 5 ) 9 0 2 – 9 0 3