Critical prognostic value of the log odds of negative lymph nodes/tumor size in rectal cancer patients

Table 4 Multivariate analyses for evaluating log odds of negative lymph nodes/tumor size effect on cancer-specific survival based on different clinicopathological factors¹

Variable	Training cohort (n = 28755)			Validation cohort (n = 12325)
	HR	95%CI	P2 value	HR	95%CI	P2 value
All	1.673	1.57-1.78	< 0.001	1.715	1.56-1.86	< 0.001
N stage
N0	1.53	1.37-1.71	< 0.001	1.422	1.20-1.68	< 0.001
N1a	1.49	1.24-1.78	< 0.001	1.73	1.26-2.36	0.001
N1b	1.42	1.21-1.65	< 0.001	1.61	1.28-2.04	< 0.001
N1c	1.68	0.96-2.92	0.069	2.12	0.98-4.60	0.057
N2a	1.64	1.40-1.93	< 0.001	1.7	1.33-2.18	< 0.001
N2b	1.55	1.34-1.79	< 0.001	1.37	1.10-1.71	0.005
T stage
T1	1.69	1.47-1.95	< 0.001	1.96	1.19-3.22	0.008
T2	1.42	1.16-1.73	0.001	1.6	1.18-2.16	0.003
T3	1.63	1.56-1.80	< 0.001	1.653	1.48-1.85	< 0.001
T4a	1.51	1.18-1.94	0.001	1.64	1.12-2.40	0.011
T4b	1.22	0.97-1.53	0.084	1.52	1.04-2.21	0.03
TNM stage
I	1.68	1.54-1.87	< 0.001	1.59	1.13-2.23	0.007
II	1.55	1.37-1.75	< 0.001	1.36	1.12-1.65	0.002
III	1.73	1.60-1.87	< 0.001	1.79	1.60-2.02	< 0.001
Sex
Male	1.722	1.59-1.86	< 0.001	1.715	1.52-1.94	< 0.001
Female	1.588	1.44-1.76	< 0.001	1.715	1.47-1.99	< 0.001
Age, yr
≤ 60	1.884	1.71-2.08	< 0.001	1.936	1.67-2.25	< 0.001
> 60	1.554	1.44-1.68	< 0.001	1.598	1.42-1.80	< 0.001
Differentiation
G1	1.268	0.94-1.72	0.125	1.549	1.03-2.33	0.035
G2	1.62	1.50-1.75	< 0.001	1.678	1.49-1.89	< 0.001
G3	1.967	1.73-2.23	< 0.001	1.859	1.53-2.26	< 0.001
Location
Rectum	1.647	1.53-1.77	< 0.001	1.613	1.44-1.81	< 0.001
Rectosigmoid junction	1.73	1.55-1.93	< 0.001	2.018	1.70-2.39	< 0.001
CEA
High	1.735	1.56-1.93	< 0.001	1.761	1.50-2.07	< 0.001
Normal	1.701	1.52-1.91	0	1.7	1.42-2.02	0
Preoperative RT
Yes	1.522	1.38-1.68	< 0.001	1.42	1.22-1.66	< 0.001
No	1.782	1.65-1.93	< 0.001	1.92	1.70-2.16	< 0.001
Chemotherapy
Yes	1.68	1.56-1.81	< 0.001	1.662	1.49-1.86	< 0.001
No	1.62	1.44-1.82	< 0.001	1.774	1.49-2.11	< 0.001
ELNs
0-10	1.415	1.29-1.56	< 0.001	1.439	1.24-1.67	< 0.001
11-20	1.79	1.61-2.00	< 0.001	2.10	1.78-2.48	< 0.001
> 20	3.30	2.64-4.14	< 0.001	2.61	1.83-3.70	< 0.001

¹Log odds of negative lymph nodes/tumor size was treated as categorical variable, and the high group as reference.

²P values were adjusted for sex, age, race, tumor-node-metastasis stage, location, preoperative radiotherapy, carcinoembryonic antigen, differentiation and chemotherapy as covariates.

CI: Confidence interval; CEA: Carcinoembryonic antigen; HR: Hazard ratio; RT: Radiotherapy; TNM: Tumor-node-metastasis; ELNs: Examined lymph nodes.