Laparoscopic vs open D2 gastrectomy for locally advanced gastric cancer: A meta-analysis

Table 1 Characteristics and quality of studies included in the meta-analysis

Publication	Study design	Cases (L/O)	Type of gastrectomy	Type of laparoscopy	Mean follow-up (mo)	Matching criteria1	Quality score
Shinohara et al[32]	Non-RCT	186/123	DG, TG, PG	TLG	48.8	1, 2, 3, 4, 7, 8, 9	8
Kim et al[31]	Non-RCT	88/88	DG, TG, PG	LAG	L: 53.7; O: 58.1	1, 2, 3, 4, 5, 7	8
Wang et al[30]	Non-RCT	210/180	DG, TG, PG	LAG	L: median 24; O: median 26	1, 2, 3, 4, 5	7
Sato et al[29]	Non-RCT	32/118	DG, TG, PG	LAG	43	1	7
Hamabe et al[28]	Non-RCT	66/101	DG, TG	LAG	L: 30.4; O: 53.5	1, 2, 3, 4, 7, 9	6
Chen et al[27]	Non-RCT	224/112	DG, TG	LAG	NS	1, 2, 3, 4, 6, 7, 8	7
Zang et al[26]	Non-RCT	156/156	TG	LAG	NS	1, 2, 3, 4, 6, 8	6
Shuang et al[25]	Non-RCT	35/35	DG	LAG	L: 36.5; O: 38.5	5, 8	6
Scatizzi et al[24]	Non-RCT	30/30	DG	TLG	18	1, 2, 3, 4, 6	7
Cai et al[23]	RCT	49/47	DG, TG, PG	LAG	22.1	1, 2, 3, 4, 5, 6, 7	RCT
Huang et al[22]	Non-RCT	66/69	DG	LAG	Range: 1-19	1, 2, 3, 4, 6, 7, 8	7
Du et al[21]	Non-RCT	82/94	TG	LAG	2.5	1, 2, 3, 4, 5, 7	7
Du et al[20]	Non-RCT	78/90	DG	LAG	25.2	1, 2, 3, 4, 5, 6, 7	7
Hur et al[19]	Non-RCT	26/25	DG	LAG	29.0	1, 2, 3, 4, 5, 7, 8, 9	7

¹Matching criteria: 1 = age; 2 = sex; 3 = pathologic tumor-node-metastasis stage; 4 = type of gastrectomy; 5 = resection margin; 6 = tumor size; 7 = histologic type; 8 = reconstruction; 9 = adjuvant treatment. DG: Distal gastrectomy; L: Laparoscopic gastrectomy; LAG: Laparoscopy-assisted gastrectomy; NS: Not stated; O: Open gastrectomy; PG: Proximal gastrectomy; RCT: Randomized controlled trial; TG: Total gastrectomy; TLG: Total laparoscopic gastrectomy.

Table 2 Meta-analysis results of endpoints from all available studies

Measured outcome	Studies (n)	Patients (n)	OR, WMD, or HR	95%CI		P	Heterogeneity test		Pr >|z|
							I2	P
Operative outcomes
Operative time	13	2300	57.06	41.87	72.25	< 0.00001	90%	< 0.00001	0.502
Intraoperative blood loss	11	2064	-137.87	-164.41	-111.33	< 0.00001	90%	< 0.00001	0.533
PO outcomes
PO analgesic consumption	4	441	-1.94	-2.50	-1.38	< 0.00001	77%	0.005	0.308
Time to first ambulation	5	977	-1.03	-1.90	-0.16	0.02	97%	< 0.00001	1.000
Time to first flatus	9	1588	-0.98	-1.30	-0.66	< 0.00001	89%	< 0.00001	0.536
Time to first oral intake	6	987	-0.85	-1.67	-0.03	0.04	86%	< 0.00001	1.000
Length of PO hospital day	10	1782	-3.08	-4.38	-1.78	< 0.00001	88%	< 0.00001	0.721
Overall morbidity	13	2284	0.78	0.61	0.99	0.04	14%	0.30	0.161
Anastomotic stenosis	12	2108	0.89	0.36	2.16	0.79	0%	0.74	0.308
Anastomotic leakage	13	2284	0.74	0.36	1.50	0.40	0%	0.80	1.000
Duodenal stump leakage	13	2284	1.12	0.42	3.01	0.82	0%	0.83	1.000
Pancreatic fistula/ pancreatitis	13	2284	0.75	0.37	1.52	0.42	0%	0.91	0.308
Intra-abdominal bleeding	13	2284	0.99	0.41	2.38	0.98	0%	0.83	1.000
Ileus	12	2108	0.56	0.21	1.46	0.23	0%	0.73	1.000
Wound problems	13	2284	0.56	0.34	0.93	0.03	0%	0.66	0.152
Pneumonia	13	2284	0.38	0.21	0.71	0.002	17%	0.29	1.000
Reoperation	7	1289	1.58	0.58	4.31	0.37	0%	0.63	1.000
Mortality	13	2284	0.69	0.21	2.26	0.54	0%	0.64	-
Oncologic outcomes
Lymph nodes harvested (n)	13	2526	-0.11	-2.72	2.50	0.94	95%	< 0.00001	0.537
Tumor recurrence/metastasis	8	1587	0.79	0.60	1.04	0.09	20%	0.27	0.035
Local/lymphatic recurrence	5	853	0.79	0.46	1.34	0.38	0%	0.41	0.296
Peritoneal recurrence	5	853	1.20	0.70	2.07	0.50	0%	0.50	0.296
Distant metastasis	5	853	0.67	0.42	1.07	0.09	45%	0.12	0.089
Three-year DFS	4	703	1.02	0.64	1.61	0.94	0%	0.88	-
Three-year overall survival	8	1363	0.87	0.59	1.27	0.46	0%	0.99	-
Five-year DFS	3	652	1.02	0.66	1.57	0.92	0%	0.67	-
Five-year overall survival	3	652	0.79	0.46	1.34	0.38	0%	0.90	-

DFS: Disease-free survival; HR: Hazard ratio; OR: Odds ratio; PO: Postoperative; WMD: Weighted mean difference.

Table 3 Ongoing randomized controlled trials comparing laparoscopic and open D2 gastrectomy for advanced gastric cancer

Contact	Country	Sample size	Type of cancer	Start date	Completion date
Li et al48]	China	1056	Locally AGC	2012/9/1	2018/6/1
Shi et al49]	China	328	Locally AGC	2010/2/1	2015/2/1
Huang et al50]	China	111	AGC	2011/11/1	Not stated
Han et al51]	South Korea	1050	Locally AGC	2011/10/1	2016/9/1
Kim et al52]	South Korea	204	Locally AGC	2010/6/1	2016/12/1
Kim et al53]	South Korea	124	Locally AGC	2008/8/1	2013/7/1
Tsuyoshi et al54]	Japan	500	Locally AGC	2009/11/1	Not stated