Clinical value of regional lymph node sorting in gastric cancer

Table 1 Baseline data of gastric cancer cases in the regional sorting group and non-sorting group

	Regional sorting group (n = 324)	Non-sorting group (n = 337)	χ²	P value
Surgery			1.727	0.422
Proximal gastrectomy	19	27
Distal gastrectomy	177	189
Total gastrectomy	128	121
Tumor location			2.744	0.254
U	46	38
M	92	85
L	186	214
Immersion depth			2.071	0.558
T1	69	60
T2	42	38
T3	19	21
T4	194	218
Differentiation degree			2.891	0.089
DCA	181	166
UCA	143	171

U: Upper third; M: Middle third; L: Lower third; DCA: Differentiated carcinoma; UCA: Undifferentiated carcinoma.

Table 2 Comparison of the number of lymph nodes and the number of positive lymph nodes between the regional sorting group and non-sorting group

	Pieces, median (interquartile range)		Z	P value
	Regional sorting group	Non-sorting group
The number of lymph nodes detected	32.5 (24.0, 42.0)	21.0 (17.0, 28.0)	-10.775	< 0.001
Number of positive lymph nodes	2.0 (0.0, 9.0)	3.0 (0.0, 9.0)	-0.172	0.863

Table 3 Binary logistic regression analysis of risk factors of lymph node metastasis in the second dissection station (n = 123)

	B	SE	Wald	df	P value	OR	95%CI
							Upper	Lower
Tumor location
U			1.067	2	0.587
M	-0.087	0.460	0.036	1	0.850	0.917	0.372	2.258
L	-0.346	0.421	0.675	1	0.411	0.708	0.310	1.615
Immersion depth
T1			5.468	3	0.141
T2	1.872	0.829	5.092	1	0.024	6.500	1.279	33.034
T3	1.504	0.850	3.132	1	0.077	4.500	0.851	23.801
T4	1.464	0.865	4.567	1	0.033	4.324	1.129	16.557
Differentiation degree
DCA/UCA	0.415	0.282	2.201	1	0.138	1.515	0.875	2.621
The number of positive lymph nodes (pieces)
≤ 6/> 6	1.707	0.305	31.284	1	< 0.001	5.514	3.031	10.029

OR: Odds ratio; CI: Confidence interval; U: Upper third; M: Middle third; L: Lower third; DCA: Differentiated carcinoma; UCA: Undifferentiated carcinoma; df: Degree of freedom.

Table 4 Multivariable logistic regression analysis of risk factors of lymph node metastasis in the second dissection station (n = 123)

	B	SE	Wald	df	P value	OR	95%CI
							Upper	Lower
Tumor location
U			0.601	2	0.741
M	-0.299	0.511	0.344	1	0.558	0.741	0.273	2.017
L	-0.358	0.463	0.599	1	0.439	0.699	0.282	1.732
Immersion depth
T1			4.710	3	0.194
T2	1.817	0.875	4.316	1	0.038	6.153	1.108	34.160
T3	0.956	0.922	1.075		0.300	2.601	0.427	15.852
T4	0.884	0.735	1.445	1	0.229	2.420	0.573	10.223
Differentiation degree
DCA/UCA	0.124	0.323	0.147	1	0.701	1.132	0.601	2.130
The number of positive lymph nodes (pieces)
≤ 6/> 6	1.718	0.322	28.541	1	< 0.001	5.576	2.968	10.473
Constant	-1197	0.829	2086	1	0.149	0.302

The Hosmer-Lemshaw test results showed good fit for the multifactorial logistic regression (P = 0.611).

OR: Odds ratio; CI: Confidence interval; U: Upper third; M: Middle third; L: Lower third; DCA: Differentiated carcinoma; UCA: Undifferentiated carcinoma; df: Degree of freedom.