Perioperative serum carcinoembryonic antigen: Powerful marker for prognostic prediction and adjuvant chemotherapy decision-making in patients with stage II and III colorectal cancer

Table 4 Univariate and multivariate stepwise Cox regression analysis (stepped by Akaike information criterion) analyses of overall survival in validation cohort

Variables	Level	Univariate analysis			Multivariate analysis
		HR	95%CI	P value	HR	95%CI	P value
Sex	Female (reference = male)	0.9700	0.7330-1.2900	0.8340
Age	Age (continuous)	1.0400	1.0200-1.0500	< 0.001	1.0339	1.0192-1.0489	< 0.001
Weight	Weight (continuous)	0.9930	0.9800-1.0000	0.2410
Height	Height (continuous)	0.9780	0.9610-0.9960	0.0191	0.9828	0.9649-1.0011	0.0650
Smoking	Positive (reference = negative)	0.9580	0.7070-1.3000	0.7840
Drinking	Positive (reference = negative)	0.7210	0.4920-1.0600	0.0946
Ileus	Positive (reference = negative)	1.2500	0.8420-1.8500	0.2680	1.5257	0.9942-2.3413	0.0532
Diabetes	Positive (reference = negative)	1.5100	1.0200-2.2600	0.0420
Hypertension	Positive (reference = negative)	1.4300	1.0500-1.9700	0.0256
Differentiation	Moderate (reference = well)	0.4860	0.3470-0.6820	< 0.001	0.5418	0.3803-0.7720	0.0007
	Poor (reference = well)	0.6200	0.3450-1.1100	0.1100	0.8004	0.4386-1.4608	0.4683
Signet-ring cell carcinoma	Positive (reference = negative)	5.2500	2.4600-11.200	< 0.001
Mucinous carcinoma	Positive (reference = negative)	1.1200	0.7730-1.6100	0.5590	1.0618	0.7103-1.5873	0.7699
Location	Left colon (reference = rectum)	0.8850	0.6230-1.2600	0.4950	0.8688	0.5923-1.2744	0.4718
	Right colon (reference = rectum)	1.0900	0.7730-1.5500	0.6130	0.9103	0.6058-1.3680	0.6512
Perineural invasion	Positive (reference = negative)	1.4300	1.0200-2.0200	0.0403	1.1350	0.7867-1.6376	0.4982
Vascular cancer embolus	Positive (reference = negative)	2.5600	1.7400-3.7500	< 0.001	1.9304	1.2780-2.9159	0.0018
Microsatellite stability	MSS (reference = MSI-H)	0.5320	0.2400-1.1800	0.1200
	No detection (reference = MSI-H)	0.7360	0.3440-1.5700	0.4270
AJCC stage	Stage III (reference = stage II)	2.0500	1.5500-2.7100	< 0.001	1.7645	1.3127-2.3717	0.0002
Pre-CEA	Pre-CEA (continuous)	1.0030	1.0020-1.0040	< 0.001
Post-CEA	Post-CEA (continuous)	1.0020	1.001-1.0030	0.0005	1.0015	1.0004-1.0025	0.0058
Pre-CA 19-9	Pre-CA 19-9 (continuous)	1.0000	1.0000-1.0000	< 0.001
Post-CA 19-9	Post-CA 19-9 (continuous)	1.0000	1.0000-1.0000	< 0.001

pre-CEA: Preoperative carcinoembryonic antigen; post-CEA: Postoperative carcinoembryonic antigen; AJCC: American Joint Committee on Cancer; CI: Confidence interval; HR: Hazard ratio; MSI-H: Microsatellite instability-high; MSS: Microsatellite stable.