Lymph node pick up by separate stations: Option or necessity?

Table 1 Patient characteristics n (%)

	All patients(n = 1112)	Group A(n = 401)	Group B(n = 711)	P
Gender
Female	448 (40.29)	144 (35.91)	304 (42.76)	0.0254
Male	664 (59.71)	257 (64.09)	407 (57.24)
Age (yr)
≤ 75	621 (55.85)	176 (43.89)	445 (62.59)	< 0.0001
> 75	491 (44.15)	225 (56.11)	266 (37.41)
Charlson score
0	869 (78.15)	312 (77.80)	557 (78.34)	0.5067
1	195 (17.54)	68 (16.96)	127 (17.86)
≥ 2	48 (4.32)	21 (5.24)	27 (3.80)
Procedure
Partial gastrectomy	674 (60.61)	257 (64.09)	417 (58.65)	0.0746
Total gastrectomy	438 (39.39)	144 (35.91)	294 (41.35)
Lymph nodes
N0	426 (38.45)	72 (43.22)	254 (35.77)	0.0126
N1	176 (15.88)	67 (16.83)	109 (15.35)
N2	180 (16.25)	65 (16.33)	115 (16.20)
N3a	200 (18.05)	63 (15.83)	137 (19.30)
N3b	126 (11.37)	31 (7.79)	95 (13.38)
Missing	4	3	1
No. lymph nodes removed
< 16	389 (34.98)	250 (62.34)	139 (19.55)	< 0.0001
≥ 16	723 (65.02)	151 (37.66)	572 (80.45)
T
T1	232 (20.86)	80 (19.95)	152 (21.38)	0.008
T2	162 (14.57)	59 (14.71)	103 (14.49)
T3	317 (28.51)	94 (23.44)	223 (31.36)
T4	401 (36.06)	168 (41.90)	233 (32.77)
Margin		25	156
Infiltrated	76 (8.16)	28 (7.45)	48 (8.65)	0.5111
Not infiltrated	855 (91.84)	348 (92.55)	507 (91.35)
Missing	181
Lauren classification
Intestinal	807 (74.24)	291 (75.58)	516 (73.50)	0.4532
Diffuse/mixed	280 (25.76)	94 (24.42)	186 (26.50)
Missing	25	16	9

Table 2 Hazard ratios and 95%CI from multivariate Cox regression models

Parameter		HR	95%CI		P
No. specimens sent to pathologist	Group A vs Group B	1.239	1.053	1.458	0.0098
Gender	M vs F	1.235	1.046	1.457	0.0127
Age, yr	> 75 vs ≤ 75	2.190	1.858	2.582	< 0.0001
T	2 vs 1	1.202	0.843	1.715	0.3087
	3 vs 1	1.957	1.438	2.663	< 0.0001
	4 vs 1	3.410	2.518	4.618	< 0.0001
N	+ vs -	2.166	1.753	2.676	< 0.0001
Type of procedure	Total vs partial	1.327	1.132	1.556	0.0005
Lauren classification	Diffuse-mixed vs intestinal	1.256	1.051	1.500	0.0119

HR: Hazard ratios.

Table 3 Lymph node status distribution by number of lymph nodes dissected and groups considered in the study n (%)

	Group A		Group B
	< 16 lymph nodes1dissected	≥16 lymph nodesdissected	< 16 lymph nodesdissected	≥16 lymph nodes2dissected
Lymph nodes -	132 (76.7)	40 (23.3)	59 (23.2)	195 (76.8)
Lymph nodes +	115 (50.9)	111 (49.1)	80 (17.5)	376 (82.5)
	P < 0.0001		P = 0.067

¹Information missing for 3 patients;

²Information missing for 1 patient.