Laparoscopic vs open total gastrectomy for advanced gastric cancer following neoadjuvant therapy: A propensity score matching analysis

Table 1 Patients and tumors’ clinical and pathological characteristics before and after propensity score matching

Variable	All patients		P value	Matched patients		P value
	LTG (n = 78)	OTG (n = 107)		LTG (n = 69)	OTG (n = 69)
Age (yr)	52.7 ± 16.1	56.0 ± 12.0	0.120	53.42 ± 13.4	53.9 ± 12.7	0.828
Gender n (%)
Male	61 (78.2)	78 (72.9)	0.409	53 (76.8)	52 (75.4)	0.842
Female	17 (21.8)	29 (27.1)		16 (23.2)	17 (24.6)
BMI (kg/m2)	22.6 ± 3.1	23.7 ± 3.7	0.028	22.6 ± 3.1	22.8 ± 3.3	0.750
ASA n (%)
1-2	74 (94.9)	99 (92.5)	0.522	65 (94.2)	64 (92.8)	1.000
3	4 (5.1)	8 (7.5)		4 (5.8)	5 (7.2)
The history of abdominalsurgery n (%)
Yes	10 (12.8)	19 (17.8)	0.362	8 (11.6)	13 (18.8)	0.236
No	68 (87.2)	88 (82.2)		61 (88.4)	56 (81.2)
Tumor location n (%)			0.775			0.698
Upper	30 (38.5)	35 (37.6)		28 (25.0)	22 (25.0)
Middle	25 (32.1)	42 (39.3)		23 (33.3)	26 (37.7)
Lower	9 (11.5)	12 (11.2)		7 (10.1)	10 (14.5)
More than two position or total	14 (17.9)	18 (16.8)		11 (15.9)	11 (15.9)
Clinical T stage n (%)			0.402			0.784
2	3 (3.8)	1 (0.9)		3 (4.3)	1 (1.4)
3	19 (24.4)	26 (24.3)		17 (24.6)	18 (26.1)
4	56 (71.8)	80 (74.8)		49 (71.0)	50 (72.5)
Clinical N stage n (%)			0.404			0.619
0	1 (1.3)	5 (4.7)		1 (1.4)	3 (4.3)
1-3	77 (98.7)	102 (95.3)		68 (98.6)	66 (95.7)
Clinical TNM stage n (%)			0.966			1.000
II	4 (5.1)	6 (5.6)		4 (5.8)	4 (5.8)
III	73 (93.6)	100 (93.5)		64 (92.8)	65 (94.2)
IVA	1 (1.3)	1 (0.9)		1 (1.4)	0 (0)
Tumor size (cm)	5.2 ± 3.1	6.0 ± 3.4	0.126	5.4 ± 3.3	5.4 ± 3.1	0.953
Nerve invasion n (%)			1.000			0.394
Yes	43 (55.1)	59 (55.1)		38 (55.1)	33 (47.8)
No	35 (44.9)	48 (44.9)		31 (44.9)	36 (52.2)
Lymph-vascular invasion n (%)			0.410			1.000
Yes	43 (55.1)	59 (55.1)		23 (33.3)	23 (33.3)
No	35 (44.9)	48 (44.9)		46 (66.7)	46 (66.7)
Differentiation n (%)			0.360			0.780
Well	4 (5.1)	3 (2.8)		1 (1.4)	2 (2.9)
Moderate	24 (30.8)	25 (23.4)		22 (31.9)	19 (27.5)
Poor	50 (64.1)	79 (73.8)		46 (66.7)	48 (69.6)
Pathological T stage n (%)			0.254			0.282
ypT0-1	8 (10.3)	8 (7.5)		6 (8.7)	7 (10.1)
ypT2	11 (14.1)	7 (6.5)		11 (15.9)	4 (5.8)
ypT3	23 (29.5)	31 (29.0)		17 (24.6)	21 (30.4)
ypT4a/4b	36 (46.2)	61 (57.0)		35 (50.7)	37 (53.6)
Pathological N stage n (%)			0.168			0.443
ypN0	26 (33.3)	26 (24.3)		23 (33.3)	18 (26.1)
ypN1	12 (15.4)	23 (21.5)		11 (15.9)	18 (26.1)
ypN2	16 (20.5)	14 (13.1)		14 (20.3)	11 (15.9)
ypN3	24 (30.8)	44 (41.1)		21 (30.4)	22 (31.9)
Distant metastasis n (%)			0.531			1.000
Yes	6 (7.7)	5 (4.7)		4 (5.8)	3 (4.3)
No	72 (92.3)	102 (95.3)		65 (94.2)	66 (95.7)
Pathological TNM stage n (%)			0.576			0.781
IIA	12 (15.4)	13 (12.1)		10 (14.5)	9 (13.0)
IIB	17 (55.1)	20 (64.5)		17 (24.6)	13 (18.8)
III	43 (55.1)	69 (64.5)		38 (55.1)	44 (63.8)
IV	6 (7.7)	5 (4.7)		4 (5.8)	3 (4.3)
Adjuvant chemotherapy n (%)			0.824			0.848
Yes	58 (74.4)	78 (72.9)		50 (72.5)	51 (73.9)
No	20 (25.6)	29 (27.1)		19 (27.5)	18 (26.1)

LTG: Laparoscopic total gastrectomy; OTG: Open total gastrectomy; BMI: Body mass index; ASA: Anesthesiologists physical status classification.

Table 2 Neoadjuvant therapy and response before and after propensity score matching

Variable	All patients		P value	Matched patients		P value
	LTG (n = 78)	OTG (n = 107)		LTG (n = 69)	OTG (n = 69)
Type n (%)			0.345			0.784
NAC	69 (88.5)	99 (92.5)		61 (88.4)	62 (89.9)
NCRT	9 (11.5)	8 (7.5)		8 (11.6)	7 (10.1)
NAC regimens n (%)			0.491			0.659
Platinum-based doublets	41 (59.4)	64 (64.6)		36 (59.0)	39 (62.9)
Epirubicin/taxane-based triplets	28 (40.6)	35 (35.4)		25 (41.0)	23 (37.1)
Cycles	3.3 ± 1.3	3.8 ± 1.8	0.086	3.3 ± 1.3	3.6 ± 1.6	0.300
Clinical response n (%)			0.939			0.859
PR	50 (64.1)	68 (63.6)		44 (63.8)	45 (65.2)
SD	28 (35.9)	39 (36.4)		25 (36.2)	24 (34.8)
Mandard TRG score n (%)			0.316			0.654
1	26 (33.3)	52 (48.6)		22 (31.9)	29 (42.0)
2	4 (5.1)	4 (3.7)		4 (5.8)	2 (2.9)
3	30 (38.5)	34 (31.8)		26 (37.7)	25 (36.2)
4	5 (6.4)	5 (4.7)		5 (7.2)	5 (7.2)
5	13 (16.7)	12 (11.2)		12 (17.4)	8 (11.6)

LTG: Laparoscopic total gastrectomy; OTG: Open total gastrectomy; NAC: Neoadjuvant chemotherapy; NCRT: Neoadjuvant chemoradiotherapy; PR: Partial response; SD: Stable disease; TRG: Tumor regression grading.

Table 3 Description of intraoperative and recovery features before and after propensity score matching

Variable	All patients		P value	Matched patients		P value
	LTG (n = 78)	OTG (n = 107)		LTG (n = 69)	OTG (n = 69)
Operation time (min)	207.6 ± 49.3	205.2 ± 52.1	0.744	204.0 ± 45.8	207.1 ± 53.1	0.713
Blood loss (mL)	197.2 ± 162.4	228.1 ± 193.4	0.252	200.6 ± 162.0	237.1 ± 194.9	0.116
Combined resection n (%)			0.139			0.245
Yes	0 (0)	4 (3.7)		0 (0)	3 (4.3)
No	78 (100)	107 (96.3)		69 (100)	66 (95.7)
Resection n (%)			0.651			1.000
R0	75 (96.2)	105 (98.1)		66 (95.7)	67 (97.1)
R1/R2	3 (3.8)	2 (1.9)		3 (4.3)	2 (2.9)
Blood transfusion n (%)			0.608			0.507
Yes	13 (16.7)	21 (80.4)		11 (15.9)	14 (20.3)
No	65 (83.3)	86 (19.6)		58 (84.1)	55 (79.7)
Length of incision (cm)	10.29 ± 4.4	21.6 ± 3.8	< 0.001	10.4 ± 4.6	21.9 ± 3.8	< 0.001
Postoperative hospital stay (d)	11.6 ± 7.0	15.1 ± 10.9	0.015	11.5 ± 7.1	16.0 ± 12.8	0.012
Dissected lymph nodes	37.7 ± 14.5	37.8 ± 17.6	0.950	37.3 ± 14.2	35.5 ± 15.9	0.465
Time to ambulation (d)	3.0 ± 1.2	3.4 ± 2.4	0.130	3.0 ± 1.3	3.4 ± 2.3	0.229
Time to first flatus (d)	4.8 ± 1.7	5.2 ± 2.3	0.235	4.9 ± 1.7	5.1 ± 1.8	0.381
Time to first liquid intake (d)	9.2 ± 5.6	10.1 ± 7.8	0.404	9.1 ± 5.6	10.7 ± 8.7	0.201
Time to removal of gastric tube (d)	5.0 ± 2.0	6.5 ± 5.0	0.008	5.1 ± 2.0	6.8 ± 5.2	0.013
Time to removal of all drainage tubes	9.7 ± 10.1	11.1 ± 11.1	0.391	9.7 ± 10.5	10.9 ± 10.3	0.488

LTG: Laparoscopic total gastrectomy; OTG: Open total gastrectomy.

Table 4 Postoperative complications before and after propensity score matching

Variable	All patients		P value	Matched patients		P value
	LTG (n = 78)	OTG (n = 107)		LTG (n = 69)	OTG (n = 69)
Complications, n (%)
Overall			0.100			0.236
Yes	15 (19.2)	32 (29.9)		14 (20.3)	20 (29.0)
No	63 (80.8)	75 (70.1)		55 (79.7)	49 (71.0)
Surgical complications
Pancreatic fistula	0 (0)	1 (0.9)	1.000	0 (0)	1 (1.4)	1.000
Abdominal bleeding	1 (1.3)	0 (0)	0.422	1 (1.4)	0 (0)	1.000
Anastomotic leakage	5 (6.4)	6 (5.6)	1.000	4 (5.8)	3 (4.3)	1.000
Wound infection	4 (5.1)	5 (4.7)	1.000	4 (5.8)	4 (5.8)	1.000
Lymphorrhagia	1 (1.3)	0 (0)	0.422	1 (1.4)	0 (0)	1.000
Intestinal obstruction	0 (0)	2 (1.9)	0.510	0 (0)	1 (1.4)	1.000
Abdominal infection	5 (6.4)	9 (8.4)	0.611	5 (7.2)	2 (2.9)	0.441
Duodenal fistula	0 (0)	1 (0.9)	1.000	0 (0)	0 (0)	NA
Gastroparesis	0 (0)	3 (2.8)	0.264	0 (0)	3 (4.3)	0.245
Medical complications
Pulmonary infection	0 (0)	6 (5.6%)	0.04	0	5 (7.2)	0.058
Arterial catheter-related infection	0 (0)	1 (0.9)	1.000	0 (0)	1 (1.4)	1.000
Renal failure	0 (0)	1 (0.9)	1.000	0 (0)	1 (1.4)	1.000
Clavien-Dindo classification n (%)			0.331			1.000
Grade I-II	12 (80.0)	20 (64.5)		11 (78.6)	14 (73.7)
Grade III-V	3 (20.0)	11 (35.5)		3 (21.4)	5 (26.3)

LTG: Laparoscopic total gastrectomy; OTG: Open total gastrectomy.

Table 5 Univariate and multivariate analysis of overall survival after propensity score matching

Variables	Univariate analysis			Multivariate analysis
	Hazard ratio	95%CI	P value	Hazard ratio	95%CI	P value
Age (yr): < 60 vs ≥ 60	0.806	0.491-1.323	0.393
Sex: Female vs Male	1.244	0.711-2.177	0.444
ASA: 1-2 vs 3	0.978	0.355-2.696	0.965
Surgery: LTG vs OTG	0.729	0.446-1.192	0.207
BMI: < 28 vs ≥ 28	1.608	0.504-5.133	0.422
Differentiation: Well/moderate vs Poor	0.713	0.416-1.224	0.220
ypT stage: T0-3 vs T4	0.446	0.267-0.746	0.002	0.520	0.308-0.877	0.014
ypN stage: N0 vs N1-3	0.401	0.217-0.741	0.004	0.431	0.227-0.821	0.010
Metastasis: M0 vs M1	0.425	0.152-1.188	0.103	0.529	0.185-1.510	0.234
Nerve invasion: Yes vs No	1.601	0.973-2.635	0.064	0.930	0.531-1.628	0.799
Lymph-vascular invasion: Yes vs No	2.046	1.236-3.388	0.005	1.155	0.623-2.140	0.647
Mandard TRG: ≤ 3 vs > 3	0.510	0.312-0.833	0.007	0.666	0.390-1.136	0.136
Postoperative complication: Yes vs No	0.635	0.338-1.193	0.158
Type of NAT: NAC vs NCRT	2.248	0.900-5.619	0.083	1.647	0.619-4.382	0.317
Resection: R0 vs R1/R2	0.385	0.120-1.237	0.109	0.357	0.110-1.154	0.085

LTG: Laparoscopic total gastrectomy; OTG: Open total gastrectomy; CI: Confidence interval; ASA: American Society of Anesthesiologist; BMI: Body mass index; TRG: Tumor regression grading; NAT: Neoadjuvant therapy; NAC: Neoadjuvant chemotherapy; NCRT: Neoadjuvant chemoradiotherapy.