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

Table 2 Univariate analysis of prognostic factors for cancer-specific survival

Variable	Training cohort (n = 28755)			Validation cohort (n = 12325)
	HR	95%CI	P value	HR	95%CI	P value
Age1	1.022	1.019-1.024	< 0.001	1.021	1.018-1.025	< 0.001
Tumor size1	1.004	1.003-1.004	< 0.001	1.003	1.002-1.003	< 0.001
NLNs1	0.971	0.967-0.974	< 0.001	0.970	0.964-0.975	< 0.001
LONS1	0.330	0.308-0.354	< 0.001	0.331	0.298-0.367	< 0.001
Sex (ref = male)	0.887	0.840-0.937	< 0.001	0.901	0.829-0.979	< 0.001
TNM (ref = stage III)
I	0.226	0.207-0.247	< 0.001	0.235	0.206-0.269	< 0.001
II	0.482	0.454-0.512	< 0.001	0.486	0.443-0.532	< 0.001
Differentiation (ref = G3 + G4)
G1	0.436	0.382-0.497	< 0.001	0.424	0.348-0.517	< 0.001
G2	0.573	0.536-0.613	< 0.001	0.566	0.511-0.626	< 0.001
Unknown	0.532	0.459-0.616	< 0.001	0.515	0.415-0.641	< 0.001
Histology (ref = MAC and SRCC)	0.537	0.488-0.590	< 0.001	0.531	0.462-0.612	< 0.001
Preoperative RT (ref = Yes)	0.884	0.836-0.934	< 0.001	0.938	0.861-1.020	0.135
Chemotherapy (ref = Yes)	0.746	0.705-0.790	< 0.001	0.776	0.712-0.845	< 0.001
Location (ref = rectum)	1.134	1.072-1.200	< 0.001	1.177	1.079-1.284	< 0.001
Race (ref = others)
White	1.045	0.955-1.143	0.336	1.013	0.883-1.162	0.853
Black	1.435	1.275-1.616	< 0.001	1.465	1.225-1.753	< 0.001
CEA (ref = High)
Normal	0.546	0.510-0.584	< 0.001	0.498	0.448-0.553	< 0.001
Unknown	0.684	0.641-0.729	< 0.001	0.686	0.622-0.756	< 0.001

¹These variables were treated as continuous data.

CI: Confidence interval; CEA: Carcinoembryonic antigen; HR: Hazard ratio; LONS: Log odds of negative lymph nodes/tumor size; MAC: Mucinous adenocarcinoma; NLNs: Negative lymph nodes; RT: Radiotherapy; SRCC: Signet-ring cell carcinoma; TNM: Tumor-node-metastasis.