Risk factors for No. 12p and No. 12b lymph node metastases in advanced gastric cancer in China

Figures & data

Table I. LN dissections in standard distal and total gastrectomies.

	Distal gastrectomy	Total gastrectomy
D1 dissection	1, 3, 4sb, 4d, 5, 6, 7	1, 2, 3, 4d, 4sa, 4sb, 5, 6, 7
D2 dissection	D1 + 8a, 9, 11, 12a	D1 + 8a, 9, 10, 11, 12a

Distal gastrectomies were performed principally for tumors located in the lower third of the stomach. For tumors in the middle third, either distal or total gastrectomies were performed, depending on the direction of tumor invasion. Total gastrectomies were used for tumors in the upper third of the stomach and those occupying the entire stomach.

Table II. Frequency of No. 12 LN metastases according to the tumor location.

	No. 12a (n, %)	No. 12p (n, %)	No. 12b (n, %)
Upper (n = 60)	4 (6.7)	3 (5.0)	0 (0.0)
Middle (n = 53)	9 (17.0)	6 (11.3)	2 (3.8)
Lower (n = 26)	5 (19.2)	4 (15.4)	2 (7.7)
Total (n = 24)	3 (12.5)	2 (8.3)	1 (4.2)

The metastatic rate of the lower stomach was higher than that of cancer of the middle or upper third of the stomach; no statistically significant differences in lymphatic metastases were found between different tumor locations of the stomach.

Table III. Characteristics in 163 patients with and without No. 12p and No. 12b LN metastases.

	Positive (n, %)	Negative (n, %)	Total (n, %)	P value
Age (years)				0.017
≤ 60	4 (26.7)	87 (58.8)	91 (55.8)
> 60	11 (73.3)	61 (41.2)	72 (44.2)
Gender				0.445
Male	9 (60.0)	103 (69.6)	112 (68.7)
Female	6 (40.0)	45 (30.4)	51 (31.3)
Borrmann type				0.005
I/II	1 (6.7)	65 (43.9)	66 (40.5)
III/IV	14 (93.3)	83 (56.1)	97 (59.5)
Tumor location				0.358
Upper	3 (20.0)	57 (38.5)	60 (36.8)
Middle	6 (40.0)	47 (31.7)	53 (32.5)
Lower	4 (26.7)	22 (14.9)	26 (16.0)
Total	2 (13.3)	22 (14.9)	24 (14.7)
Localization				0.024
Greater	2 (13.3)	43 (29.1)	45 (27.6)
Lesser	7 (46.7)	85 (57.4)	92 (56.4)
Circular	6 (40.0)	20 (13.5)	26 (16.0)
Tumor size (cm)				0.007
≤ 4	1 (6.7)	25 (16.9)	26 (16.0)
> 4,< 8	3 (20.0)	75 (50.7)	78 (47.8)
≥ 8	11 (73.3)	48 (32.4)	59 (36.2)
Depth of invasion				0.000
pT2	1 (6.7)	22 (14.9)	23 (14.1)
pT3	3 (20.0)	91 (61.5)	94 (57.7)
pT4	11 (73.3)	35 (23.6)	46 (28.2)
Histological type				0.143
Differentiated	3 (20.0)	58 (39.2)	61 (37.4)
Undifferentiated	12 (80.0)	90 (60.8)	102 (62.6)

Positive = patients with No. 12p and No. 12b LN metastases; Negative = patients without No. 12p and No. 12b LN metastases.

Table IV. Logistic regression analysis of characteristics for No. 12p and No. 12b LN metastases.

	B value	SE	Wald	P value	Hazard ratio (95% CI)
Age	1.295	0.687	3.556	0.059	3.651 (0.950–14.029)
Borrmann type	2.409	1.105	4.754	0.029	11.127 (1.276–97.034)
Localization	1.335	0.597	4.994	0.025	3.800 (1.178–12.255)
Tumor size	0.917	0.593	2.385	0.122	2.501 (0.781–8.002)
Depth of invasion	1.730	0.662	6.826	0.009	5.641 (1.541–20.655)

A logistic regression analysis was conducted for five variables (age, Borrmann type, localization, tumor size, and depth of invasion) that had been found to be significant using either Fisher's exact or chi-square tests. A logistic regression analysis showed that Borrmann type, localization, and depth of invasion were each a significant variable of No. 12p and No. 12b LN metastases (P = 0.029, P = 0.025, and P = 0.009, respectively).

Table V. Regional LNs metastases in 163 patients with No. 12p and No. 12b metastases.

	LNs metastases (n, %)	No. 12p/b metastases (n, %)	P value
No. 1	56/163 (34.4)	7/15 (46.7)	0.292
No. 2	33/117 (28.2)	5/15 (33.3)	0.869
No. 3	93/163 (57.1)	13/15 (86.7)	0.015
No. 4sa	17/117 (14.5)	3/15 (20.0)	0.801
No. 4sb	23/163 (14.1)	5/15 (33.3)	0.064
No. 4d	35/163 (21.5)	6/15 (40.0)	0.133
No. 5	27/163 (16.6)	9/15 (60.0)	0.000
No. 6	12/163 (7.4)	3/15 (20.0)	0.148
No. 7	45/163 (27.6)	9/15 (60.0)	0.003
No. 8a	19/163 (11.7)	4/15 (26.7)	0.139
No. 9	8/163 (4.9)	3/15 (20.0)	0.027
No. 10	18/117 (15.4)	3/15 (20.0)	0.883
No. 11	16/163 (9.8)	2/15 (13.3)	0.631
No. 12a	21/163 (12.9)	8/15 (53.3)	0.000

No. 1 = right paracardial; No. 2 = left paracardial; No. 3 = lesser curvature; No. 4a = along short gastric vessels; No. 4sb = along left gastroepiploic vessels; No. 4d = along right gastroepiploic vessels; No. 5 = suprapyloric; No. 6 = infrapyloric; No. 7 = along left gastric artery; No. 8a = anterosuperior group; No. 9 = around celiac axis; No. 10 = splenic hilum; No. 11 = along splenic artery; No. 12a = along hepatic artery in the hepatoduodenal ligament.

Table VI. Logistic regression analysis of LN metastasis for No. 12p and No. 12b LN metastases.

	B value	SE	Wald	P value	Hazard ratio (95% CI)
No. 3	1.442	0.813	3.141	0.076	4.227 (0.859–20.815)
No. 5	1.935	0.702	7.590	0.006	6.921 (1.748–27.409)
No. 7	0.764	0.682	1.254	0.263	2.147 (0.564–8.177)
No. 9	-0.083	1.020	0.007	0.935	0.920 (0.125–6.789)
No. 12a	2.428	0.843	8.304	0.004	11.340 (2.174–59.146)

Significant LNs were extracted for further analysis, carried out using a logistic regression method. A logistic regression analysis showed that the metastasis to the No. 5 and No. 12a LNs were each a significant variable for No. 12p and 12b LN metastases (P = 0.006 and P = 0.004, respectively).

Figure 1. Survival in 163 patients with and without No. 12p and No. 12b LN metastases. There were significant differences in the 5-year survival rate between patients with and without No. 12p and No. 12b LN metastases (13.3% versus 35.1%, P = 0.022).