By Christina Frangou

San Francisco—Robotic gastrectomy can match the long-term clinical and oncologic outcomes of laparoscopic surgery in patients with early gastric cancer, a large single-center study has shown.

Robotic surgery does not appear, however, to provide superior outcomes, which many experts argue will be necessary to justify the added costs of robotic surgery.

At the American Society of Clinical Oncology’s 2013 Gastrointestinal Cancers Symposium, researchers from Severance Hospital, part of the Yonsei University Hospital System in Seoul, South Korea, presented a retrospective analysis of their large prospectively designed database for gastric cancer.

Overall (OS) and relapse-free survival were almost identical for patients who underwent laparoscopic surgery or robotic surgery, in the 862 patients who underwent minimally invasive surgery for histologically proven gastric adenocarcinoma between July 2005 and December 2009.

five-year survival reached 94% in the robotic group, a nonsignificant half percent higher than among laparoscopic patients. In both groups, disease-free survival hovered around 92%.

“Robotic surgery has acceptable long-term oncology outcomes compared with the current laparoscopic procedures and is an effective alternative to laparoscopy, which is quite difficult,” said lead author Woo Jin Hyung, MD, PhD, assistant professor of surgery, Yonsei University College of Medicine, also in Seoul.

Robotic surgery “may be an easy way for us to perform complex procedures,” he said. He added that studies with more advanced patients and with data on cost-effectiveness and quality of life are needed.

The study included 317 patients who underwent robotic surgery, making it the largest reported series of robotic gastric cancer procedures, and 545 patients who underwent laparoscopic surgery.

With a median follow-up of 46 months, postoperative recurrences occurred in 5.4% of patients in the robotic group and 3.6% in the laparoscopic arm, which was not statistically significant (P=0.745).

The same team of researchers previously reported that patients who received robotic gastrectomy had better short-term and comparable oncologic outcomes compared with laparoscopic gastrectomy (Arch Surg 2011;146:1086-1092).

Donald E. Low, MD, head of thoracic surgery at Seattle’s Virginia Mason Medical Center, commended the study for “outstanding clinical volume,” “breathtaking” surgical outcomes and “unparalleled” oncologic outcomes.

Dr. Low noted, however, that the study does not address important questions regarding robotic surgery: How do the functional outcomes compare between the two approaches? How do the costs compare?

“I think the conclusion you can take from this is that robotic surgery is equivalent but not better than laparoscopic surgery for major cancer procedures. Robotic gastrectomy currently provides no measurable outcome benefits and is likely, almost assuredly, more expensive.”

In the future, costs of robotic surgery are expected to decrease as more robotic systems come to market, although it is currently not known when other systems will be available or how more market competition will affect prices.

In this study, patients were billed for the added surcharge of the robotic procedures, although details on costs were not reported. Even without financial specifics, it is assumed the cost associated with robotic gastric cancer surgery would be much higher than for laparoscopic surgery. A previously reported study from a different Korean hospital looked at costs for robotic versus conventional laparoscopic surgery for rectal cancer and found that robotic surgery was associated with increased hospital charges ($14,647 vs. $9,978), greater payments by patients ($11,540 vs. $3,956) and reduced hospital profits ($689 vs. $1,671) (World J Surg 2012;36:2722-2729).

Robotic surgery has been shown in other studies to hold some advantages over laparoscopic surgery, including a shorter learning curve for conventionally trained oncologic surgeons; better visualization of structures including lymph nodes and resection margins; and 360-degree range of operator motion, said Jennifer F. Tseng, MD, chief of surgical oncology, Beth Israel Deaconess Medical Center Cancer Center, Boston.

“The importance of this abstract is that in the near future, minimally invasive oncologically sound gastric and upper GI [gastrointestinal] surgery, through robotic assistance, may be available to a much wider segment of the population with cancer than is currently the case.”

The study consisted predominantly of patients with early-stage cancers. Around 80% of patients in the cohort had stage I disease, 10.5% were stage II and 6% were stage III.

Analysis revealed no significant difference in cancer recurrence or OS between the two procedures for all stages. OS for stage II patients reached 90% in the robotic arm and 88.2% in the laparoscopic arm (P=0.817); for stage III patients, five-year survival was 65.1% and 70%, respectively (P=0.985).

Patients in the robotic arm of the study were younger (54.5 vs. 59.3 years; P<0.001) and were more likely to have a total resection (26.8 vs. 19.7%; P=0.016). In keeping with studies of robotic approaches, the robot was associated with significantly longer operating times (219.0±45.5 vs. 149.0±41.4 minutes; P<0.001).