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

Table 5 Univariate and multivariate stepwise Cox regression analysis (stepped by Akaike information criterion) of disease-free survival in validation cohort

Variables	Level	Univariate analysis			Multivariate analysis
		HR	95%CI	P value	HR	95%CI	P value
Sex	Female (reference = male)	1.1300	0.8830-1.4500	0.3300
Age	Age (continuous)	1.0300	1.0200-1.0400	< 0.001	1.0268	1.0140-1.0398	< 0.001
Weight	Weight (continuous)	0.9910	0.9800-1.0000	0.0908
Height	Height (continuous)	0.9770	0.9610-0.9920	0.0034	0.9783	0.9624-0.9944	0.0084
Smoking	Positive (reference = negative)	0.9360	0.7140-1.2300	0.6330
Drinking	Positive (reference = negative)	0.7840	0.5630-1.0900	0.1500
Ileus	Positive (reference = negative)	1.3000	0.9090-1.8600	0.1500	1.5541	1.0495-2.3014	0.0277
Diabetes	Positive (reference = negative)	1.5400	1.0800-2.2000	0.0163	1.3728	0.9581-1.9672	0.0842
Hypertension	Positive (reference = negative)	1.4600	1.1100-1.9400	0.0076
Differentiation	Moderate (reference = well)	0.5430	0.3990-0.7390	0.0001	0.6312	0.4566-0.8726	0.0054
	Poor (reference = well)	0.7020	0.4190-1.1800	0.1790	0.9253	0.5435-1.5752	0.7748
Signet-ring cell carcinoma	Positive (reference = negative)	3.3600	1.5800-7.1200	0.0016
Mucinous carcinoma	Positive (reference = negative)	0.9560	0.6750-1.3500	0.8010
Location	Left colon (reference = rectum)	0.9310	0.6820-1.2700	0.6550	0.9343	0.6638-1.3148	0.6965
	Right colon (reference = rectum)	1.0100	0.7370-1.3900	0.9350	0.9149	0.6299-1.3287	0.6403
Perineural invasion	Positive (reference = negative)	1.3500	0.9910-1.8400	0.0573	1.1080	0.7997-1.5350	0.5377
Vascular cancer embolus	Positive (reference = negative)	2.2500	1.5700-3.2300	< 0.001	1.8155	1.2354-2.6679	0.0024
Microsatellite stability	MSS (reference = MSI-H)	0.6150	0.2960-1.2800	0.1930
	No detection (reference = MSI-H)	0.7550	0.3710-1.5300	0.4370
AJCC stage	Stage III (reference = stage II)	1.8800	1.4600-2.4100	< 0.001	1.6515	1.2721-2.1439	0.0002
Pre-CEA	Pre-CEA (continuous)	1.0030	1.0010-1.0040	< 0.001
Post-CEA	Post-CEA (continuous)	1.0010	1.0010-1.0020	0.0007	1.0012	1.0003-1.0022	0.0100
Pre-CA 19-9	Pre-CA 19-9 (continuous)	1.0000	1.0000-1.0000	< 0.001	1.0014	1.0005-1.0024	0.0041
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.