Impact of perioperative Helicobacter pylori eradication therapy on long-term survival after distal gastrectomy for gastric cancer

Table 1 Comparison of baseline demographic characteristics between the two groups, n (%)/mean ± SD

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	t/χ2	P value
Age (years)	59.41 ± 6.84	58.24 ± 6.15	1.565	0.119
Sex			1.948	0.163
Male	105 (73.43)	84 (65.63)
Female	38 (26.57)	44 (34.38)
BMI (kg/m2)	23.02 ± 2.91	22.68 ± 2.53	1.094	0.275
Charlson Comorbidity Index	2.11 ± 0.68	2.04 ± 0.62	1.018	0.310
Smoking history	56 (39.16)	41 (32.03)	1.494	0.222
Alcohol history	50 (34.97)	35 (27.34)	1.822	0.177

BMI: Body mass index.

Table 2 Comparison of tumor pathological characteristics between the two groups, n (%)

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	t/χ2	P value
Tumor size (cm), mean ± SD	4.38 ± 1.44	4.52 ± 1.48	0.787	0.432
Tumor location			0.472	0.790
Antrum	108 (75.52)	92 (71.88)
Gastric angle	23 (16.08)	24 (18.75)
Lower body	12 (8.39)	12 (9.38)
Differentiation			1.226	0.268
Well/moderate	80 (55.94)	63 (49.22)
Poor	63 (44.06)	65 (50.78)
Lauren classification			0.659	0.719
Intestinal	76 (53.15)	68 (53.13)
Diffuse	40 (27.97)	40 (31.25)
Mixed	27 (18.88)	20 (15.63)
pTNM stage			1.383	0.501
I	37 (25.87)	38 (29.69)
II	47 (32.87)	46 (35.94)
III	59 (41.26)	44 (34.38)
Lymphovascular invasion	52 (36.36)	41 (32.03)	0.562	0.453

pTNM: Pathological tumor-node-metastasis.

Table 3 Comparison of surgical parameters between the two groups, n (%)/mean ± SD

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	t/χ2	P value
Surgical approach			0.056	0.813
Laparoscopic	98 (68.53)	86 (67.19)
Open	45 (31.47)	42 (32.81)
Reconstruction type			1.478	0.478
B-I	64 (44.76)	48 (37.50)
B-II	52 (36.36)	52 (40.63)
R-Y	27 (18.88)	28 (21.88)
Number of lymph nodes harvested	31.48 ± 6.52	32.58 ± 5.98	1.511	0.132
Postoperative hospital stay (days)	11.16 ± 3.24	10.52 ± 2.88	1.829	0.069

B-I: Billroth I reconstruction; B-II: Billroth II reconstruction; R-Y: Roux-en-Y reconstruction.

Table 4 Comparison of perioperative Helicobacter pylori eradication and postoperative Helicobacter pylori status, n (%)

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	χ2	P value
Completed eradication regimen	-	128 (100.00)	271.000	< 0.001
Eradication successful	-	117 (91.41)	230.017	< 0.001
Helicobacter pylori status at 6 months postop			142.668	< 0.001
Negative	27 (18.88)	117 (91.41)
Positive	116 (81.12)	11 (8.59)
Spontaneous clearance	27 (18.88)	-	26.842	< 0.001

Table 5 Comparison of 30-day postoperative complications between the two groups, n (%)

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	χ2	P value
Overall complications	29 (20.28)	20 (15.63)	0.988	0.320
Clavien-Dindo ≥ grade III	12 (8.39)	7 (5.47)	0.885	0.347
Anastomotic leakage	5 (3.50)	2 (1.56)	0.382	0.536
Intra-abdominal infection	9 (6.29)	5 (3.91)	0.786	0.375
Wound infection	8 (5.59)	4 (3.13)	0.973	0.324
Delayed gastric emptying	10 (6.99)	8 (6.25)	0.060	0.806

Clavien-Dindo: Clavien-Dindo Classification of Surgical Complications.

Table 6 Comparison of remnant gastric lesions at 1 year postoperatively, n (%)/mean ± SD

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	t/χ2	P value
Atrophy score (0-3)	1.86 ± 0.60	1.44 ± 0.48	7.077	< 0.001
Intestinal metaplasia score (0-3)	1.67 ± 0.56	1.26 ± 0.42	8.045	< 0.001
Bile reflux grade			0.409	0.938
Absent	98 (68.53)	92 (71.88)
Mild	30 (20.98)	24 (18.75)
Moderate	12 (8.39)	10 (7.81)
Severe	3 (2.10)	2 (1.56)
Remnant gastritis severity			7.978	0.046
Absent	28 (19.58)	38 (29.69)
Mild	64 (44.76)	62 (48.44)
Moderate	36 (25.17)	22 (17.19)
Severe	15 (10.49)	6 (4.69)
Anastomotic ulcer	15 (10.49)	4 (3.13)	5.619	0.018

Table 7 Comparison of adjuvant chemotherapy completion (stage II/III patients), n (%)/mean ± SD

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	t/χ2	P value
Chemotherapy regimen			0.319	0.853
XELOX	59 (56.19)	48 (53.33)
SOX	38 (36.19)	36 (40.00)
Other	8 (7.62)	6 (6.67)
Chemotherapy delay	29 (28.71)	14 (15.56)	4.103	0.043
Dose reduction	24 (23.76)	10 (11.11)	4.645	0.031
Completed cycles	5.68 ± 1.48	6.22 ± 1.16	2.832	0.005
Relative dose intensity (%)	85.28 ± 10.86	89.54 ± 7.88	3.165	0.002
Planned cycle completion	67 (66.34)	74 (82.22)	8.205	0.004
Discontinuation due to adverse events	20 (19.80)	8 (8.89)	4.067	0.044

XELOX: Capecitabine plus oxaliplatin; SOX: S-1 plus oxaliplatin.

Table 8 Comparison of long-term oncologic outcomes between the two groups, n (%)

Parameters	Non-eradication group (n = 143)	Eradication group (n = 128)	χ2	P value
5-year OS rate (%)	80.42	91.41	6.618	0.010
All-cause death	28 (19.58)	11 (8.59)
5-year DFS rate (%)	72.73	85.94	7.097	0.008
Recurrence or metastasis	39 (27.27)	18 (14.06)
Local recurrence	14 (9.79)	6 (4.69)
Regional recurrence	10 (6.99)	5 (3.91)
Distant metastasis	15 (10.49)	7 (5.47)
Metachronous gastric cancer	11 (7.69)	2 (1.56)	5.557	0.018
Gastric cancer-specific death	22 (15.38)	8 (6.25)	5.725	0.017

OS: Overall survival; DFS: Disease-free survival.

Table 9 Multivariate Cox regression analysis of factors associated with overall survival and disease-free survival

Variable	β	SE	Wald χ2	P value	HR	95%CI
OS
Eradication (yes vs no)	-0.598	0.285	4.405	0.036	0.551	0.310-0.964
Age (per year)	0.032	0.018	3.160	0.075	1.036	0.993-1.075
Sex (male vs female)	0.128	0.248	0.267	0.606	1.143	0.701-1.853
pTNM stage (III vs I-II)	0.852	0.314	7.361	0.007	2.347	1.274-4.340
Differentiation (poor vs well/moderate)	0.318	0.242	1.728	0.189	1.375	0.863-2.211
Lymphovascular invasion (yes vs no)	0.452	0.256	3.117	0.078	1.571	0.955-2.592
DFS
Eradication (yes vs no)	-0.511	0.252	4.113	0.043	0.604	0.362-0.984
Age (per year)	0.018	0.017	1.121	0.290	1.025	0.996-1.050
Sex (male vs female)	0.146	0.228	0.410	0.522	1.166	0.741-1.813
pTNM stage (III vs I-II)	0.824	0.278	8.787	0.003	2.287	1.327-3.931
Differentiation (poor vs well/moderate)	0.262	0.218	1.444	0.230	1.306	0.859-1.992
Lymphovascular invasion (yes vs no)	0.378	0.234	2.610	0.106	1.462	0.926-2.315

β: Regression coefficient; HR: Hazard ratio; CI: Confidence interval; OS: Overall survival; DFS: Disease-free survival; pTNM: Pathological tumor-node-metastasis.