LETTER TO THE EDITOR Robotic Versus Laparoscopic Hepatectomy: What Is the Best Minimally Invasive Approach? To the Editor: e read with great interest the article written by Tsung et al,1 and we wish to congratulate them for the large series of robot-assisted and laparoscopic liver resections (RALR and LLR) included in the study. The authors compared 2 groups of patients who underwent RALR and LLR in a 1:2 matched analysis highlighting a substantial equivalence of results between the 2 techniques with the exception of completion of a greater number of purely laparoscopic liver resections in the robotic group. Although the study was well conducted and nicely written, there are a few points that need to be elucidated by the authors. We notice that the techniques for parenchymal transection are not described. Referring to a previous publication from the same group, the linear staplers are preferentially used for laparoscopic liver resections and the crush-clamping technique using endowristed bipolar forceps and clips is the preferred transection method in the RALR.2 Inherent differences between the 2 techniques risk hampering results of the study, especially if the authors referred to the operative time as one of the main parameters to compare the 2 procedures. In fact, stapled liver resection is invariably associated with a shorter transection time, particularly in right and left hepatectomy where a straight resection line is followed. The authors compare 3 different type of laparoscopic resections: pure, hybrid, and hand-assisted with RALR, which is in fact “fully laparoscopic.” Indeed, only 49.1% of the total laparoscopic procedures have been done in a pure laparoscopic fashion, compared with the 93% of the robotic group. These differences make the laparoscopic group absolutely heterogeneous, confounding the results such as operative time, estimated blood loss, or complication rates. Moreover, indications for pure, hybrid, and hand-assisted approach are not clearly stated in the text. With regard to the hand-assisted approach, the authors omitted to explain how
W
Disclosure: The authors declare no funding and no conflicts of interest. C 2014 Wolters Kluwer Health, Inc. All Copyright rights reserved. ISSN: 0003-4932/14/26202-e0070 DOI: 10.1097/SLA.0000000000000701
e70 | www.annalsofsurgery.com
many cases were the result of an unsuccessful attempt at pure laparoscopic surgery, preventing our understanding of the real conversion rate in that group. In addition, the low percentage of pure laparoscopic procedures is in stark contrast to that reported by Nguyen et al3 in their review, where the rate of pure laparoscopic liver resection was 95.1% (2667/2804). Moreover, we are surprised that a pure laparoscopic major hepatectomy was possible in only 7.1% of cases versus 81% of the RALR group. The rate of major hepatectomies in both groups is surprisingly high, taking into account the actual trend to spare parenchyma in both primary and metastatic liver lesions (at least in Europe) and indicates a scarce use of the technical advantages of the robotic system to perform parenchymalsaving resections in the posterosuperior segments (PS), as shown in previous studies.4,5 Finally, only the number of major or minor resections is reported, without a description of the resection type (ie, wedge, segmentectomy, bisegmentectomy, etc) or the site of resected lesions (anterolateral vs posterosuperior segments). It is well known that resection of lesions in the PS are associated with higher blood loss, longer operative time, and a higher risk of conversion in respect to those in the anterior segments.6–8 A detailed analysis of these 2 subgroups could possibly detect some differences between the 2 techniques. In our experience, we have found that despite higher conversion rate and blood loss, robotic-assisted surgery allowed the resection of more liver lesions, especially those located in the PS segments, facilitating parenchymasaving surgery with a complication rate comparable with a laparoscopic approach.5 A separate comparison between laparoscopic and robotic resections in the anterior and PS segments would thus offer a more realistic picture of the real potentials and limits of both techniques. Roberto Montalti, MD, PhD Department of General and Hepatobiliary Surgery Ghent University Hospital Medical School De Pintelaan, Ghent, Belgium Alberto Patriti, MD, PhD Department of General and Minimally Invasive Surgery S. Matteo degli Infermi Hospital Spoleto, Italy Roberto Ivan Troisi, MD, PhD Department of General and Hepatobiliary Surgery Ghent University Hospital Medical School De Pintelaan, Ghent, Belgium [email protected]
REFERENCES 1. Tsung A, Geller DA, Sukato DC, et al. Robotic versus laparoscopic hepatectomy: a matched comparison. Ann Surg. 2014;259:549–555. 2. Packiam V, Bartlett DL, Tohme S, et al. Minimally invasive liver resection: robotic versus laparoscopic left lateral sectionectomy. J Gastrointest Surg. 2012;16:2233–2238. 3. Nguyen KT, Gamblin TC, Geller DA. World review of laparoscopic liver resection—2,804 patients. Ann Surg. 2009;250:831–841. 4. Casciola L, Patriti A, Ceccarelli G, et al. Robotassisted parenchymal-sparing liver surgery including lesions located in the posterosuperior segments. Surg Endosc. 2011;25:3815–3824. 5. Troisi RI, Patriti A, Montalti R, et al. Robot assistance in liver surgery: a real advantage over a fully laparoscopic approach? Results of a comparative biinstitutional analysis. Int J Med Robot. 2013;9:160– 166. 6. Cho JY, Han HS, Yoon YS, et al. Feasibility of laparoscopic liver resection for tumors located in the posterosuperior segments of the liver, with a special reference to overcoming current limitations on tumor location. Surgery. 2008;144:32–38. 7. Edwin B, Nordin A, Kazaryan AM. Laparoscopic liver surgery: new frontiers. Scand J Surg. 2011;100:54–65. 8. Troisi RI, Montalti R, Van Limmen JG, et al. Risk factors and management of conversions to an open approach in laparoscopic liver resection: analysis of 265 consecutive cases. HPB (Oxford). 2014;16: 75–82.
Reply: n the article, “Robotic Versus Laparoscopic Hepatectomy: A Matched Comparison,” we sought to present our institution’s series comparing laparoscopic and robotic liver resections.1 Our findings demonstrate that both laparoscopic and robotic approaches displayed similar safety and operative outcomes excluding operative time. In the accompanying Letter to the Editor, we thank Montalti et al for their interest in our article and we provide a reply to stimulate discussion and future studies on this hot topic. Minimally invasive approaches to liver resection have been increasingly used in the past decade. We agree that laparoscopic liver resection comprises a diverse group of techniques including pure laparoscopic, handassisted laparoscopic, hybrid technique, and robotic approach (which is the relatively newest approach according to the literature). In our study, most minor laparoscopic liver resections were completed with a pure laparoscopic approach similar to our robotic cohort. Until the robot liver experience was gained over the past 3 years, our practice had favored using a hand-assisted or hybrid technique for major hepatectomies. Indeed, at
I
Disclosure: The authors declare no conflicts of interest and no source of funding. 10.1097/SLA.0000000000000702
Annals of Surgery r Volume 262, Number 2, August 2015
Copyright © 2014 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Annals of Surgery r Volume 262, Number 2, August 2015
the 2008 Louisville consensus meeting on laparoscopic liver surgery, it was commented that there are a variety of laparoscopic approaches appropriate for liver resection, with European centers favoring pure laparoscopy whereas many surgeons from North America have adopted the hand-assisted or hybrid approaches. Although the majority of our major hepatectomies were completed with the hand-assisted or hybrid techniques, this did not represent an unsuccessful attempt at pure laparoscopic surgery. These are our preferred methods for more extensive liver resections at our institution and the hand port is placed as the first step of the operation or the hybrid approach is planned from the onset. Failure to complete our cases in a minimally invasive manner resulted in conversion to open in 8% of our laparoscopic cases, which did not differ from the conversion rate of 7% for our robotic cases. Although our laparoscopic group was heterogeneous, we have previously shown that the minimally invasive approaches result in improved outcomes compared with the open liver resection2,3 and thus sought to make a similar comparison of our laparoscopic group as a whole with the robotic group. Interestingly, although our data suggest that the benefit of a robotic approach is the ability to complete a major hemihepatectomy in a pure minimally invasive approach, we could not demonstrate any difference in perioperative outcomes compared with our laparoscopic group consisting of both hand-assisted and hybrid techniques. This suggests that patients undergoing a pure laparoscopic hemihepatectomy with the robotic approach do equally well as those undergoing laparoscopic hemihepatectomy with a hand-assisted or hybrid approach. Intuition would suggest that a “pure” laparoscopic or robotic approach is better for the patient than a hand-assisted or hybrid approach, but we have not been able to demonstrate that effect. This does not mean that all surgeons necessarily agree with that statement, and, indeed, there is differing opinions among the 5 experienced hepatobiliarypancreatic surgeons in our group as to which approach is best. Perhaps, the clinical differences between a pure laparoscopic approach (with or without the robot) and a hand-assisted approach are so small that a clinical study
would require a large number of patients to establish this statistically. Perhaps, additional data will be gleaned from the upcoming Second International Laparoscopic Liver Consensus Conference, which will occur in October 2014 in Morioka, Japan. For the current time, it seems which minimally invasive approach is used depends on surgeons’ preference based on the specifics of each case. Furthermore, we analyzed the location of resected lesions to determine whether the robot facilitated resections of posterosuperior segments in a minimally invasive manner. We found that 20 patients (35%) in the robotic group had tumors located in posterosuperior locations compared with 55 patients (48%) in the laparoscopic group. There was no difference in location of the tumors and the type of resection required (major vs minor) using either robotic or laparoscopic approach. Although Montalti et al have suggested that robotic-assisted surgery allowed increased parenchyma-saving resections of posterosuperior segments, we did not find this potential benefit in our series. This is likely due to the fact that our experience with tumors in these locations can be resected using techniques such as transthoracic port sites and lateral positioning to facilitate access to the posterosuperior segments. In addition, we have found the hand port useful in resecting these lesions due to its greater ability to mobilize and retract the liver than in pure laparoscopy. The surgical techniques used for our laparoscopic and robotic liver resections are different. We use linear staplers more for our laparoscopic liver resections than in crushclamping techniques using clips and suturing for robotic resections. We agree with Montalti et al that this could contribute to the shorter operative times in our laparoscopic cohort. In addition, the longer times for the robotic cases could be attributed to the additional time required to dock the robot, to exchange instruments, and to reposition or redock the instruments if the viewing field necessitated change. Finally, our institution also prefers a parenchyma-sparing operation (especially with metastatic colorectal cancer or neuroendocrine tumors) whenever possible. However, we have not been able to show that the robot allows an increased ability to
C 2014 Wolters Kluwer Health, Inc. All rights reserved.
Letter to the Editor
perform a parenchyma-sparing operation as Montalti et al report in their Letter to the Editor. We thank Montalti et al for their insightful comments and agree that further studies should be undertaken to overcome the limitations of our retrospective study at a single institution. A major finding in our study was that a higher percentage of anatomic hemihepatectomies could be accomplished in a pure laparoscopic approach with the robot, but we acknowledge that this was not a randomized study and that inherent selection bias and surgeon preference exist despite the patients being well-matched between groups. Does the robot really provide advantages in laparoscopic liver surgery? Although our study demonstrates that robotic-assisted surgery is comparable in safety and feasibility with the laparoscopic approach, there were no significant perioperative benefits comparing robotic with hand-assisted or hybrid laparoscopic approaches. In addition, the downside of added cost and longer operative times compared with a laparoscopic approach is also an important consideration.4 However, as technology for the robotic platform improves with diminished costs, the robot may potentially offer further benefits in minimally invasive liver surgery. Allan Tsung, MD David A. Geller, MD Division of Hepatobiliary and Pancreatic Surgery Department of Surgery University of Pittsburgh Medical Center Pittsburgh, PA [email protected]
REFERENCES 1. Tsung A, Geller DA, Sukato DC, et al. Robotic versus laparoscopic hepatectomy: a matched comparison. Ann Surg. 2014;259:549–555. 2. Nguyen KT, Gamblin TC, Geller DA. World review of laparoscopic liver resection—2,804 patients. Ann Surg. 2009;250:831–841. 3. Nguyen KT, Marsh JW, Tsung A, et al. Comparative benefits of laparoscopic vs open hepatic resection: a critical appraisal. Arch Surg. 2011;146:348–356. 4. Packiam V, Bartlett DL, Tohme S, et al. Minimally invasive liver resection: robotic versus laparoscopic left lateral sectionectomy. J Gastrointest Surg. 2012;16:2233–2238.
www.annalsofsurgery.com | e71
Copyright © 2014 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
W
Disclosure: The authors declare no funding and no conflicts of interest. C 2014 Wolters Kluwer Health, Inc. All Copyright rights reserved. ISSN: 0003-4932/14/26202-e0070 DOI: 10.1097/SLA.0000000000000701
e70 | www.annalsofsurgery.com
many cases were the result of an unsuccessful attempt at pure laparoscopic surgery, preventing our understanding of the real conversion rate in that group. In addition, the low percentage of pure laparoscopic procedures is in stark contrast to that reported by Nguyen et al3 in their review, where the rate of pure laparoscopic liver resection was 95.1% (2667/2804). Moreover, we are surprised that a pure laparoscopic major hepatectomy was possible in only 7.1% of cases versus 81% of the RALR group. The rate of major hepatectomies in both groups is surprisingly high, taking into account the actual trend to spare parenchyma in both primary and metastatic liver lesions (at least in Europe) and indicates a scarce use of the technical advantages of the robotic system to perform parenchymalsaving resections in the posterosuperior segments (PS), as shown in previous studies.4,5 Finally, only the number of major or minor resections is reported, without a description of the resection type (ie, wedge, segmentectomy, bisegmentectomy, etc) or the site of resected lesions (anterolateral vs posterosuperior segments). It is well known that resection of lesions in the PS are associated with higher blood loss, longer operative time, and a higher risk of conversion in respect to those in the anterior segments.6–8 A detailed analysis of these 2 subgroups could possibly detect some differences between the 2 techniques. In our experience, we have found that despite higher conversion rate and blood loss, robotic-assisted surgery allowed the resection of more liver lesions, especially those located in the PS segments, facilitating parenchymasaving surgery with a complication rate comparable with a laparoscopic approach.5 A separate comparison between laparoscopic and robotic resections in the anterior and PS segments would thus offer a more realistic picture of the real potentials and limits of both techniques. Roberto Montalti, MD, PhD Department of General and Hepatobiliary Surgery Ghent University Hospital Medical School De Pintelaan, Ghent, Belgium Alberto Patriti, MD, PhD Department of General and Minimally Invasive Surgery S. Matteo degli Infermi Hospital Spoleto, Italy Roberto Ivan Troisi, MD, PhD Department of General and Hepatobiliary Surgery Ghent University Hospital Medical School De Pintelaan, Ghent, Belgium [email protected]
REFERENCES 1. Tsung A, Geller DA, Sukato DC, et al. Robotic versus laparoscopic hepatectomy: a matched comparison. Ann Surg. 2014;259:549–555. 2. Packiam V, Bartlett DL, Tohme S, et al. Minimally invasive liver resection: robotic versus laparoscopic left lateral sectionectomy. J Gastrointest Surg. 2012;16:2233–2238. 3. Nguyen KT, Gamblin TC, Geller DA. World review of laparoscopic liver resection—2,804 patients. Ann Surg. 2009;250:831–841. 4. Casciola L, Patriti A, Ceccarelli G, et al. Robotassisted parenchymal-sparing liver surgery including lesions located in the posterosuperior segments. Surg Endosc. 2011;25:3815–3824. 5. Troisi RI, Patriti A, Montalti R, et al. Robot assistance in liver surgery: a real advantage over a fully laparoscopic approach? Results of a comparative biinstitutional analysis. Int J Med Robot. 2013;9:160– 166. 6. Cho JY, Han HS, Yoon YS, et al. Feasibility of laparoscopic liver resection for tumors located in the posterosuperior segments of the liver, with a special reference to overcoming current limitations on tumor location. Surgery. 2008;144:32–38. 7. Edwin B, Nordin A, Kazaryan AM. Laparoscopic liver surgery: new frontiers. Scand J Surg. 2011;100:54–65. 8. Troisi RI, Montalti R, Van Limmen JG, et al. Risk factors and management of conversions to an open approach in laparoscopic liver resection: analysis of 265 consecutive cases. HPB (Oxford). 2014;16: 75–82.
Reply: n the article, “Robotic Versus Laparoscopic Hepatectomy: A Matched Comparison,” we sought to present our institution’s series comparing laparoscopic and robotic liver resections.1 Our findings demonstrate that both laparoscopic and robotic approaches displayed similar safety and operative outcomes excluding operative time. In the accompanying Letter to the Editor, we thank Montalti et al for their interest in our article and we provide a reply to stimulate discussion and future studies on this hot topic. Minimally invasive approaches to liver resection have been increasingly used in the past decade. We agree that laparoscopic liver resection comprises a diverse group of techniques including pure laparoscopic, handassisted laparoscopic, hybrid technique, and robotic approach (which is the relatively newest approach according to the literature). In our study, most minor laparoscopic liver resections were completed with a pure laparoscopic approach similar to our robotic cohort. Until the robot liver experience was gained over the past 3 years, our practice had favored using a hand-assisted or hybrid technique for major hepatectomies. Indeed, at
I
Disclosure: The authors declare no conflicts of interest and no source of funding. 10.1097/SLA.0000000000000702
Annals of Surgery r Volume 262, Number 2, August 2015
Copyright © 2014 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
Annals of Surgery r Volume 262, Number 2, August 2015
the 2008 Louisville consensus meeting on laparoscopic liver surgery, it was commented that there are a variety of laparoscopic approaches appropriate for liver resection, with European centers favoring pure laparoscopy whereas many surgeons from North America have adopted the hand-assisted or hybrid approaches. Although the majority of our major hepatectomies were completed with the hand-assisted or hybrid techniques, this did not represent an unsuccessful attempt at pure laparoscopic surgery. These are our preferred methods for more extensive liver resections at our institution and the hand port is placed as the first step of the operation or the hybrid approach is planned from the onset. Failure to complete our cases in a minimally invasive manner resulted in conversion to open in 8% of our laparoscopic cases, which did not differ from the conversion rate of 7% for our robotic cases. Although our laparoscopic group was heterogeneous, we have previously shown that the minimally invasive approaches result in improved outcomes compared with the open liver resection2,3 and thus sought to make a similar comparison of our laparoscopic group as a whole with the robotic group. Interestingly, although our data suggest that the benefit of a robotic approach is the ability to complete a major hemihepatectomy in a pure minimally invasive approach, we could not demonstrate any difference in perioperative outcomes compared with our laparoscopic group consisting of both hand-assisted and hybrid techniques. This suggests that patients undergoing a pure laparoscopic hemihepatectomy with the robotic approach do equally well as those undergoing laparoscopic hemihepatectomy with a hand-assisted or hybrid approach. Intuition would suggest that a “pure” laparoscopic or robotic approach is better for the patient than a hand-assisted or hybrid approach, but we have not been able to demonstrate that effect. This does not mean that all surgeons necessarily agree with that statement, and, indeed, there is differing opinions among the 5 experienced hepatobiliarypancreatic surgeons in our group as to which approach is best. Perhaps, the clinical differences between a pure laparoscopic approach (with or without the robot) and a hand-assisted approach are so small that a clinical study
would require a large number of patients to establish this statistically. Perhaps, additional data will be gleaned from the upcoming Second International Laparoscopic Liver Consensus Conference, which will occur in October 2014 in Morioka, Japan. For the current time, it seems which minimally invasive approach is used depends on surgeons’ preference based on the specifics of each case. Furthermore, we analyzed the location of resected lesions to determine whether the robot facilitated resections of posterosuperior segments in a minimally invasive manner. We found that 20 patients (35%) in the robotic group had tumors located in posterosuperior locations compared with 55 patients (48%) in the laparoscopic group. There was no difference in location of the tumors and the type of resection required (major vs minor) using either robotic or laparoscopic approach. Although Montalti et al have suggested that robotic-assisted surgery allowed increased parenchyma-saving resections of posterosuperior segments, we did not find this potential benefit in our series. This is likely due to the fact that our experience with tumors in these locations can be resected using techniques such as transthoracic port sites and lateral positioning to facilitate access to the posterosuperior segments. In addition, we have found the hand port useful in resecting these lesions due to its greater ability to mobilize and retract the liver than in pure laparoscopy. The surgical techniques used for our laparoscopic and robotic liver resections are different. We use linear staplers more for our laparoscopic liver resections than in crushclamping techniques using clips and suturing for robotic resections. We agree with Montalti et al that this could contribute to the shorter operative times in our laparoscopic cohort. In addition, the longer times for the robotic cases could be attributed to the additional time required to dock the robot, to exchange instruments, and to reposition or redock the instruments if the viewing field necessitated change. Finally, our institution also prefers a parenchyma-sparing operation (especially with metastatic colorectal cancer or neuroendocrine tumors) whenever possible. However, we have not been able to show that the robot allows an increased ability to
C 2014 Wolters Kluwer Health, Inc. All rights reserved.
Letter to the Editor
perform a parenchyma-sparing operation as Montalti et al report in their Letter to the Editor. We thank Montalti et al for their insightful comments and agree that further studies should be undertaken to overcome the limitations of our retrospective study at a single institution. A major finding in our study was that a higher percentage of anatomic hemihepatectomies could be accomplished in a pure laparoscopic approach with the robot, but we acknowledge that this was not a randomized study and that inherent selection bias and surgeon preference exist despite the patients being well-matched between groups. Does the robot really provide advantages in laparoscopic liver surgery? Although our study demonstrates that robotic-assisted surgery is comparable in safety and feasibility with the laparoscopic approach, there were no significant perioperative benefits comparing robotic with hand-assisted or hybrid laparoscopic approaches. In addition, the downside of added cost and longer operative times compared with a laparoscopic approach is also an important consideration.4 However, as technology for the robotic platform improves with diminished costs, the robot may potentially offer further benefits in minimally invasive liver surgery. Allan Tsung, MD David A. Geller, MD Division of Hepatobiliary and Pancreatic Surgery Department of Surgery University of Pittsburgh Medical Center Pittsburgh, PA [email protected]
REFERENCES 1. Tsung A, Geller DA, Sukato DC, et al. Robotic versus laparoscopic hepatectomy: a matched comparison. Ann Surg. 2014;259:549–555. 2. Nguyen KT, Gamblin TC, Geller DA. World review of laparoscopic liver resection—2,804 patients. Ann Surg. 2009;250:831–841. 3. Nguyen KT, Marsh JW, Tsung A, et al. Comparative benefits of laparoscopic vs open hepatic resection: a critical appraisal. Arch Surg. 2011;146:348–356. 4. Packiam V, Bartlett DL, Tohme S, et al. Minimally invasive liver resection: robotic versus laparoscopic left lateral sectionectomy. J Gastrointest Surg. 2012;16:2233–2238.
www.annalsofsurgery.com | e71
Copyright © 2014 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.
