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Table 1. Advantages and disadvantages of RG vs. LG are summarized
Articulated devices RG favor
3D image RG favor
Tremor suppression RG favor
ergonomics RG favor
Intraoperative blood loss Equivalent
Morbidity rate Equivalent
Mortality rate Equivalent
Medical expense LG favor
Operation time LG favor
RG: robotic gastrectomy; LG: laparoscopic gastrectomy

been published, the cost for RG is not yet reimbursed by government, and therefore patients or hospitals
have to pay additional fees . In contrast, medical expense for LG is partially covered by national insurance
[17]
systems, and the cost burden on patients and hospitals is obviously less than for RG. The additional fee
for RG differs between surgeries depending on how many disposable and re-usable instruments are used.
Previously, some comparative studies investigated the difference in medical expense between RG and LG
and reported that RG expenses were approximately twice as great [18-21] . In a prospective comparative study
conducted in Korea, significantly higher total cost in the RG group (US$13,432) than the LG group (US$8090)
was also reported . However, if medical expenses associated with RG decrease in the future, they will no
[14]
longer be an absolute disadvantage of RG.

COMPARISON OF SHORT-TERM SURGICAL OUTCOMES BETWEEN RG AND LG
Short-term surgical outcomes between RG and LG have been compared in many retrospective and a few
prospective studies [9,14-20,22-44] . Among short-term surgical outcomes, intraoperative blood loss, the duration of
surgery, the number of retrieved lymph nodes, the incidence of postoperative complications, and the length
of postoperative hospital stay are thought to reflect surgical quality, and were assessed in most studies.

Intraoperative blood loss was generally equivalent or less during RG than LG [Table 2]. The magnified
fine three-dimensional view attained in RG enables surgeons to recognize even very small vessels, and
with articulated devices, they can surely stanch bleeding. However, the reported statistically significant
differences in intraoperative bleeding between LG and RG were generally less than 100 mL except for one
report from Korea , and it is unclear whether the difference is clinically significant of not. Statistically
[38]
significant more blood loss in RG was also reported in two Japanese studies, but the differences were less
than 20 mL [33,41] .

The duration of surgery is significantly longer in RG than in LG in all report, and the difference was
statistically significant in most series [Table 3]. Although the difference ranged from 14 to 124 min, it took
RG generally approximately 60 min more operation time than LG. There are several probable explanations
for longer operation time in RG. Firstly, it takes 15 to 30 min, known as docking time, to prepare before an
operator begins the surgery at a console. Secondly, during RG, a surgeon uses four robotic arms, which is
less than the average number of five ports used during conventional LG. Although an additional port for an
assistant can be used in RG, it is under the assistant’s not the surgeon’s control, and is sometimes useless due
to collisions with robotic arms. As a result, it becomes difficult to make a fine surgical field, particularly in
patients with high visceral fat volume or advanced disease, and therefore might cause longer operation time.

The number of retrieved lymph nodes was reported to be almost equal between RG and LG. The duration
of postoperative hospital stay was also similar, although a few investigators reported that it was shorter
following RG than LG.