Table 3.

Effect of different N stages on the risk of survival outcomes

N stage	AJCC system						Proposed system
	OS		DFS		DFFS		OS		DFS		DFFS
	HR (95% CI)	P	HR (95% CI)	P	HR (95% CI)	P	HR (95% CI)	P	HR (95% CI)	P	HR (95% CI)	P
N0	1 (reference)		1 (reference)		1 (reference)		1 (reference)		1 (reference)		1 (reference)
N1	2.50 (0.72–8.71)	0.150	1.66 (0.75–3.65)	0.208	1.52 (0.61–3.79)	0.370	2.62 (0.77–8.91)	0.123	1.38 (0.63–3.03)	0.419	1.30 (0.53–3.23)	0.569
N2	4.02 (1.18–13.69)	0.026	2.29 (1.05–4.98)	0.038	2.16 (0.88–5.33)	0.093	4.39 (1.26–15.34)	0.020	3.53 (1.62–7.71)	0.002	3.39 (1.38–8.31)	0.008
N3	7.72 (2.26–26.44)	0.001	4.97 (2.28–10.83)	< 0.001	5.41 (2.22–13.16)	< 0.001	9.48 (2.75–32.69)	< 0.001	5.58 (2.52–12.38)	< 0.001	5.88 (2.37–14.61)	< 0.001

Abbreviations: AJCC American Joint Committee on Cancer, OS overall survival, DFS disease-free survival, DFFS distant failure-free survival, HR hazard ratio, CI confidence interval