Does N ratio affect survival in D1 and D2 lymph node dissection for gastric cancer?

Table 2 Comparison of 5 year survivals in dissection 1 and dissection 2 dissection groups depending on N and N ratio n (%)

N	D	n	5 YS	P value	N ratio	n	5 YS	P value
N0	D1	20	6 (30.0%)	0.172	0	20	6 (30.0%)	0.389
	D2	26	13 (50.0%)			26	13 (50.0%)
N1	D1	32	4 (12.5%)	0.047	1	29	4 (13.8%)	0.070
	D2	47	15 (31.9%)			44	13 (29.5%)
N2	D1	40	6 (15.0%)	0.044	2	39	5 (12.8%)	0.192
	D2	37	1 (2.7%)			32	3 (9.4%)
N3	D1	4	NA	NA	3	16	1 (6.3%)	0.267
	D2	10	NA			44	0

D1: D1 lymphadenectomy; D2: D2 lymphadenectomy; N ratio: Node ratio; 5 YS: Five years survival; NA: Not available.