Robot-assisted laparoscopic vs open gastrectomy for gastric cancer: Systematic review and meta-analysis

Table 1 Baseline characteristics of include studies and quality assessment

Ref.	Year	Country	Type of study	Total patients (n)	Group	n	Sex (M/F)	P value	Age (mean ± SD)	P value	BMI (mean ± SD)	P value	Quality assessment
Kim et al[21]	2010	South Korea	Retrospective clinical trial	28	RAG	16	10/6	NS	53.8 ± 15.6 56.0 ± 12.4	NS	21.3 ± 3.4 25.2 ± 1.9	> 0.05	6 stars1
					OG	12	9/3
Caruso et al[22]	2011	Italy	Retrospective clinical trial	149	RAG	29	18/11	NS	64.8 ± 12.4 65.1 ± 11	NS	27 ± 3 28 ± 4	NS	6 stars1
					OG	120	65/55
Huang et al[23]	2012	China	Retrospective clinical trial	625	RAG	39	19/20	< 0.05	65.1 ± 15.9 67.9 ± 30.1	NS	24.2 ± 3.7 23.7 ± 3.6	NS	5 stars1
					OG	586	406/180
Kim et al[24]	2012	South Korea	Retrospective clinical trial	4978	RAG	436	265/171	NS	54.2 ± 12.5 57.7 ± 11.8	< 0.05	23.6 ± 3.1 23.8 ± 8.0	NS	5 stars1
					OG	4542	3008/1534
Procopiuc et al[25]	2015	Romania	Retrospective clinical trial	47	RAG	18	13/5	NS	59.1 ± 13.7 60.1 ± 12.4	NS	26.0 ± 3.24 24.8 ± 4.58	NS	6 Stars1
					OG	29	21/8
Wang et al[26]	2016	China	Randomized clinical trial	296	RAG	151	109/42	NS	57.5 ± 12.7 55.9 ± 13.1	NS	22.1 ± 2.9 21.3 ± 2.5	NS	3 points2
					OG	145	89/56

¹According to the NOS (Newcastle-Ottawa Scale) classification;

²According to Jadad’s scale for reporting randomized controlled trials. RAG: Robot-assisted gastrectomy; OG: Open gastrectomy; NS: Not statistically significant.

Table 2 Main perioperative data of the included studies

Ref.	Open conversion (%)	Group	Operation time (min ± SD)1	P value	Blood loss (mL ± SD)1	P value	Harvested nodes (n ± SD)1	P value	Morbidity (%)	P value	Mortality (%)	P value	Hospital stay (d ± SD)1	P value
Kim et al[21]	0	RAG OG	259.2 ± 38.9 126.7 ± 24.1	< 0.05	30.3 ± 15.1 78.8 ± 74.1	< 0.05	41.1 ± 10.9 43.3 ± 10.4	NS	0 20	NS	0 0	NS	5.1 ± 0.3 6.7 ± 1.4	< 0.05
Caruso et al[22]	0	RAG OG	290 ± 67 222 ± 94	< 0.05	197.6 ± 202.1 386.1 ± 95.5	< 0.05	28.0 ± 11.2 31.7 ± 15.6	NS	10.32 10.02	NS	0 3.3	NS	9.6 ± 2.8 13.4 ± 8.5	< 0.05
Huang et al[23]	NR	RAG OG	415.9 ± 101.2 331.8 ± 92.9	< 0.05	93.9 ± 89 192 ± 193	< 0.05	32 ± 13.7 34 ± 14.8	NS	15.4 14.7	NS	1.4 2.6	NS	11.3 ± 14.4 16.5 ± 13.6	< 0.05
Kim et al[24]	NR	RAG OG	226 ± 54 158 ± 52	< 0.05	85 ± 160 192 ± 193	< 0.05	40.2 ± 15.5 40.5 ± 16.6	NS	10.1 10.7	NS	0.5 0.5	NS	7.5 10.2	< 0.05
Procopiuc et al[25]	0	RAG OG	320.8 ± 85.1 243.3 ± 57.9	< 0.05	208.2 ± 139.8 564.6 ± 468.4	< 0.05	22.0 ± 8.9 25.2 ± 9.0	NS	11.12 20.72	NS	0 0	NS	8.1 ± 2.0 11.4 ± 2.9	< 0.05
Wang et al[26]	1.93	RAG OG	242.7 ± 43.8 192.4 ± 31.5	< 0.05	94.2 ± 51.5 152.8 ± 94.2	< 0.05	29.1 ± 6.7 30.1 ± 7.2	NS	9.3 10.3	NS	0 0	NS	5.7 ± 2.3 6.4 ± 2.5	< 0.05

¹Mean value;

²Major complications rate base on Clavien-Dindo classification ≥ 3, such as anastomotic and duodenal lekeage;

³Rate of patients excluded from the study analysis. RAG: Robot-assisted gastrectomy; OG: Open gastrectomy; NS: Not statistically significant difference.

Table 3 Sensitivity analysis of outcomes

Outcomes	No. of studies	Patients		WMD/OR	Analysis model	95%CI	P value	Heterogeneity
		RAG	OG					I2 (%)	P value
Operative time (min)	5[22-26]	673	5422	60.12	Random	41.31, 98.06	< 0.00001	80	0.41
Estimated blood loss (mL)	5[22-26]	673	5422	-193.78	Random	-215.77, -72.13	< 0.0001	72	0.007
Harvested lymph nodes	5[22-26]	673	5422	-1.05	Random	-2.01, 0.39	0.35	0	0.12
Overall postoperative complication	5[22-26]	673	5422	0.92	Fixed	0.61, 1.36	0.6	12	0.72
Postoperative hospital stay	5[22-26]	673	5422	-2.57	135.8 ± 133.9	-2.68, -1.56	< 0.001	0	0.54

RAG: Robot-assisted gastrectomy; OG: Open gastrectomy; WMD: Weighted mean difference; OR: Odds ratio.