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

Table 2 Univariate and multivariate stepwise Cox regression analysis (stepped by Akaike information criterion) of overall survival in training cohort

Variables	Level	Univariate analysis			Multivariate analysis
		HR	95%CI	P value	HR	95%CI	P value
Sex	Female (reference = male)	0.9630	0.8180-1.1300	0.6550
Age	Age (continuous)	1.0300	1.0200-1.0400	< 0.001	1.0330	1.0234-1.0417	< 0.001
Weight	Weight (continuous)	0.9980	0.9920-1.0000	0.5340
Height	Height (continuous)	1.0000	0.9950-1.0100	0.4010	1.0072	0.9987-1.0158	0.0950
Smoking	Positive (reference = negative)	1.0100	0.8620-1.1900	0.8890
Drinking	Positive (reference = negative)	1.1400	0.9460-1.3700	0.1690
Ileus	Positive (reference = negative)	1.3600	1.1100-1.6700	0.0032	1.3589	1.1019-1.6758	0.0041
Diabetes	Positive (reference = negative)	1.6000	1.2200-2.0900	0.0006
Hypertension	Positive (reference = negative)	1.2100	0.9210-1.5800	0.1730
Differentiation	Moderate (reference = well)	0.6260	0.2010-1.9500	0.4190	0.6163	0.1971-1.9266	0.4052
	Poor (reference = well)	0.9190	0.2920-2.8900	0.8850	0.8002	0.2535-2.5260	0.7039
Signet-ring cell carcinoma	Positive (reference = negative)	1.8500	1.1700-2.9100	0.0086
Mucinous carcinoma	Positive (reference = negative)	1.2300	1.0100-1.5000	0.0417	1.2369	1.0115-1.5125	0.0383
Location	Left colon (reference = rectum)	0.7820	0.6470-0.9450	0.0110	0.7762	0.6404-0.9407	0.0098
	Right colon (reference = rectum)	0.7540	0.6120-0.9290	0.0081	0.7744	0.6256-0.9586	0.0189
Perineural invasion	Positive (reference = negative)	1.8700	1.560-2.2400	< 0.001	1.6107	1.3309-1.9492	< 0.001
Vascular cancer embolus	Positive (reference = negative)	1.8700	1.4900-2.3400	< 0.001	1.3868	1.0981-1.7514	0.0060
Microsatellite stability	MSS (reference = MSI-H)	1.1100	0.7610-1.6100	0.5940
	No detection (reference = MSI-H)	1.6500	1.1600-2.3600	0.0056
AJCC stage	Stage III (reference = stage II)	1.9300	1.6400-2.2700	< 0.001	1.6919	1.4248-2.0090	< 0.001
Pre-CEA	Pre-CEA (continuous)	1.0030	1.0020-1.0040	< 0.001
Post-CEA	Post-CEA (continuous)	1.0010	1.0010-1.0010	< 0.001	1.0008	1.0004-1.0012	< 0.001
Pre-CA 19-9	Pre-CA 19-9 (continuous)	1.0000	1.000-1.000	0.0001
Post-CA19-9	Post-CA 19-9 (continuous)	1.0000	1.000-1.000	< 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.