Systematic review and meta-analysis of laparoscopy-assisted and open total gastrectomy for gastric cancer

Table 1 Characteristics of included studies

Ref.	Nation	Study type	Study period	Sample size		Stage	Level of lymphadenectomy	Follow-up (mo)		Level of evidence
				LATG	OTG			LATG	OTG
Kim et al[30]	South Korea	Retro	2004-2006	27	33	EC + AC	D1 + α/β, D2	NR	NR	2b
Mochiki et al[31]	Japan	Retro	1999-2007	20	18	EC + AC	D1 + β	31 (3-60)	46 (13-60)	2b
Sakuramoto et al[32]	Japan	Retro	2003-2007	30	44	EC + AC	D1 + β, D2	30		4
Kawamura et al[33]	Japan	Retro	2003-2008	46	35	EC	D2	NR	NR	4
Du et al[34]	China	Retro	2005-2009	82	94	AC	D2	25 (2-44)		2b
Kim et al[35]	South Korea	Pros	2009-2010	63	127	EC + AC	D2	NR	NR	2b
Kunisaki et al[36]	Japan	Pros	2002-2008	27	30	EC + AC	D1 + β	NR	NR	3b
Eom et al[37]	Korea	Retro	2003-2008	100	348	EC + AC	D2	52.6 (0.3-95.7)		4
Guan et al[38]	China	Pros	2007-2010	41	56	EC + AC	D2	NR	NR	3b

Retro: Retrospective observational study; Pros: Prospective observational study; EC: Early gastric cancer; AC: Advanced gastric cancer; NR: Not reported; LATG: Laparoscopy-assisted total gastrectomy; OTG: Open total gastrectomy.

Table 2 Results of meta-analysis

Outcome	No. of study	Sample size		Heterogeneity (P, I2)	Overall effect size	95%CI of overall effect	P value
		LATG	OTG
Operating time (min)	9	436	785	< 0.001, 94%	WMD = 57.68	30.48-84.88	< 0.001
Blood loss	7	309	404	< 0.001, 95%	SMD = -1.71	-2.48 - -0.94	< 0.001
Retrieved lymph nodes	9	436	785	0.09, 41%	WMD = -1.41	-3.15 - 0.32	0.11
Proximal margin (cm)	2	163	475	1.00, 0%	WMD = -0.40	-0.82 - 0.02	0.06
Distal margin (cm)	2	163	475	0.67, 0%	WMD = 0.46	-0.40 - 1.32	0.29
Analgesics given	4	221	300	< 0.001, 93%	SMD = -0.86	-1.62 - -0.11	0.02
Duration of fever (d)	2	112	138	0.47, 0%	WMD = -1.58	-1.80 - -1.37	< 0.001
Time to first flatus (d)	7	316	419	< 0.001, 91%	WMD = -0.76	-1.22 - -0.30	0.001
Time to oral intake (d)	4	161	257	0.04, 63%	WMD = -0.81	-1.26 - -0.35	< 0.001
Hospital stay (d)	8	354	691	0.02, 56%	WMD = -2.67	-3.96 - -1.38	< 0.001
Overall complications	9	436	785	0.10, 40%	RR = 0.79	0.61-1.02	0.07
Surgical complications	9	436	785	0.42, 2%	RR = 0.83	0.64-1.08	0.16
Medical complications	7	343	614	0.70, 0%	RR = 0.41	0.19-0.90	0.03
Mortality	4	229	490	0.66, 0%	RR = 0.72	0.20-2.57	0.61

WMD: Weighted mean difference; SMD: Standard mean difference; LATG: Laparoscopy-assisted total gastrectomy; OTG: Open total gastrectomy.

Table 3 Subgroup analysis for learning curve using a cut-point of 40 laparoscopy-assisted total gastrectomy cases

Outcome	No. of study	Sample size		Heterogeneity (P, I2)	Overall effect size	95%CI of overall effect	P value
		LATG	OTG
Operating time (min)
< 40 LATG cases	4	104	125	< 0.001, 95%	WMD = 81.99	1.47-162.5	0.05
> 40 LATG cases	5	332	660	< 0.001, 93%	WMD = 42.53	16.23-68.82	0.002
Blood loss
< 40 LATG cases	3	77	92	0.40, 0%	SMD = -1.22	-1.55 - -0.88	< 0.001
> 40 LATG cases	4	232	312	< 0.001, 97%	SMD = -2.07	-3.35 - -0.79	0.002
Retrieved lymph nodes
< 40 LATG cases	4	104	125	0.20, 36%	WMD = -6.12	-10.42 - -1.81	0.005
> 40 LATG cases	5	332	660	0.47, 0%	WMD = -0.50	-2.4 - 1.39	0.60

LATG: Laparoscopy-assisted total gastrectomy; OTG: Open total gastrectomy; WMD: Weighted mean difference; SMD: Standard mean difference.