Robotic surgery for hepatic neoplasms: Where does it fit in the minimally invasive surgery landscape?

Robotic surgery is commonly performed for cancers of the prostate and uterus but is still evolving for other tumors, such as colon and rectal malignancies. In 2017, more than 693,000 robotic-assisted procedures were performed in the U.S., and the overall market for surgical robotic systems was valued at more than $2.4 billion. An even more specialized tumor site being treated with robotic surgery is neoplastic disease of the liver (see Figure 1).

Figure 1. Robotic liver resection

The Second International Consensus Conference on Laparoscopic Liver Resection took place in 2014 in Japan in an effort to better define the role of laparoscopic liver resection and to develop internationally accepted guidelines, such as indications for this approach, parenchymal transection methods, and bleeding control.¹ This conference reflected the growing acceptance of minimally invasive approaches for surgical management of solid tumors traditionally thought to be too complex to be performed through any means but an open procedure. It would appear enough evidence exists to support laparoscopic procedures for hepatic tumors; however, the role of robotic surgery is unclear. Recently, a multicenter study reported long-term oncologic outcomes following robotic liver resections for primary hepatobiliary malignancies (hepatocellular carcinoma, cholangiocarcinoma, or gallbladder cancer) showing comparable outcomes to published open and laparoscopic data.²

An area needing further research

All the literature comparing laparoscopic to robotic hepatectomy have been published in the last four years, illustrating the limited extent of experience with this technique. A matched comparison of robotic and laparoscopic hepatectomy from the University of Pittsburgh, PA, demonstrated similar safety and feasibility, although the robotic approach made it possible for more major hepatectomies to be performed in a minimally invasive fashion.³ Another report published in 2015 investigated the role of robotic surgery to expand indications for minimally invasive hepatectomy and found robotics may facilitate complex liver resections and increase the number of patients who can have operations involving a less invasive approach.⁴

Between 2015 and 2018, four systematic reviews and meta-analyses were published comparing outcomes between robotic-assisted versus laparoscopic hepatectomy for liver tumors.^5-8 The results were remarkably similar in all the studies, showing no differences in surgical margin status, complication rate, or hospital stay. However, the robotic resections had longer operative time, increased intraoperative blood loss, and greater cost. One study reported a lower conversion rate to an open procedure with the robotic approach,⁸ and another review suggested potential advantages of enabling performance of more complicated minimally invasive liver resections through use of robotic surgery.⁷

The data available are certainly limited, and no definite conclusions regarding the efficacy of robotic versus laparoscopic hepatectomy can be drawn. However, based on the findings that are available, the literature has shown the two minimally invasive surgery platforms have similar outcomes, with robotic-assisted procedures having a higher cost but possibly enabling surgeons to perform more complex liver resections.

Whether it should be considered a tool or a specialized practice, robotic surgery is here to stay, and the importance of credentialing and proper training for surgeons who want to perform robotic liver resections cannot be overstressed. For now, this platform will continue to coexist with laparoscopy as a minimally invasive option. Robotic hepatic surgery is on a par with laparoscopic hepatectomy in terms of safety, feasibility, and oncologic outcomes and may have some advantages in terms of more advanced procedures. At present, almost 3,000 da Vinci Surgical Systems are in use in the U.S., and this number will continue to grow. Companies like Johnson & Johnson and Medtronic also plan to introduce their own robotic surgical systems in the near future.

Prospective clinical trials

The benefits of a minimally invasive surgical approach for hepatic neoplasms are clear, and if it can be done with no impairment in oncologic outcomes, the choice is straightforward. Whether surgeons choose a laparoscopic versus robotic approach will depend on their training, experience, and hospital robotic surgery resources.

To clarify the role of laparoscopic and robotic surgery for hepatic neoplasms, prospective clinical trials are a consideration. They have been performed to evaluate the role of minimally invasive surgery, with the most notable example being the Clinical Outcomes of Surgical Therapy (COST) trial examining results of laparoscopic versus open colectomy for cancer showing equivalent outcomes and establishing laparoscopic colectomy as an acceptable alternative to open surgery.⁹

The American College of Surgeons Oncology Group (ACOSOG) Z6051 trial compared open versus laparoscopic surgery for rectal cancer and reported laparoscopic resection did not meet criteria for non-inferiority to the open approach.¹⁰ However, the truth is both robotic and laparoscopic hepatectomy procedures have their proponents, and it may be challenging in today’s climate to perform randomized studies comparing the two modalities. New technologies have learning curves, further complicating the ability to evaluate in randomized trials. Going forward, surgeons who perform minimally invasive liver resection need to be aware of their own capabilities, critically follow their outcomes, and apply best practice guidelines based on available evidence in treating their patients with hepatic malignancies.

References

1. Wakabayashi G, Cherqui D, Geller DA, et al. Recommendations for laparoscopic liver resection: A report from the second international consensus conference held in Morioka. Ann Surg. 2015;261(4):619-629.
2. Khan S, Beard RE, Kingham PT, et al. Long-term oncologic outcomes following robotic liver resections for primary hepatobiliary malignancies: A multicenter study. Ann Surg Oncol. 2018;25(9):2652-2660.
3. Tsung A, Geller DA, Sukato DC, et al. Robotic versus laparoscopic hepatectomy: A matched comparison. Ann Surg. 2014;259(3):549-555.
4. Bonapasta SA, Bartolini I, Checcacci P, Guerra F, Coratti A. Indications for liver surgery: Laparoscopic or robotic approach. Updates Surg. 2015;67(2):117-122.
5. Montalti R, Berardi G, Patriti A, Vivarelli M, Troisi RI. Outcomes of robotic vs laparoscopic hepatectomy: A systematic review and meta-analysis. World J Gastroenterol. 2015;21(27):8441-8451.
6. Qiu J, Chen S, Chengyou D. A systematic review of robotic-assisted liver resection and meta-analysis of robotic versus laparoscopic hepatectomy for hepatic neoplasms. Surg Endosc. 2016;30(3):862-875.
7. Guerra F, Di Marino M, Coratti A. Robotic surgery of the liver and biliary tract. J Laparoendosc Adv Surg Tech A. August 17, 2018. [Epub ahead of print].
8. Guan R, Chen Y, Yang K, Ma D, Gong X, Shen B, Peng C. Clinical efficacy of robot-assisted versus laparoscopic liver resection: A meta analysis. Asian J Surg. August 28, 2018. [Epub ahead of print].
9. Clinical Outcomes of Surgical Therapy Study Group, Nelson H, Sargent DJ, et al. A comparison of laparoscopically assisted and open colectomy for colon cancer. N Engl J Med. 2004;350(20):2050-2059.
10. Fleshman J, Branda M, Sargent DJ, et al. Effect of laparoscopic-assisted resection vs open resection of stage II or III rectal cancer on pathologic outcomes: The ACOSOG Z6051 randomized clinical trial. JAMA. 2015;314(13):1346-1355.