Pretreatment Carcinoembryonic Antigen Level Serves as a Potential Biomarker to Guide Adjuvant Radiotherapy in pT4N+ Colon Cancer Patients

Table 2

Univariate and multivariate Cox analyses of the clinicopathological factors for overall survival in pT4N + colon cancer patients with elevated pretreatment CEA levels.

Variable	Univariate analysis		Multivariate analysis
	HR (95% CI)	value	HR (95% CI)	value
Histologic type
Adenocarcinoma	Reference		Reference
Mucinous	1.081 (0.973–1.202)	0.148	1.048 (0.940–1.167)	0.398
Signet ring cell	1.559 (1.304–1.864)	<0.001	1.306 (1.086–1.571)	0.005
Other	—		—
Grade
G1 + G2	Reference		Reference
G3 + G4	1.307 (1.211–1.410)	<0.001	1.234 (1.140–1.335)	<0.001
Unknown	—		—
Tumor size
<5 cm	Reference		Reference
≥5 cm	1.113 (1.030–1.202)	0.006	1.087 (1.005–1.175)	0.036
Unknown	—		—
N stage
N1	Reference		Reference
N2	1.225 (1.137–1.319)	<0.001	1.195 (1.109–1.289)	<0.001
Radiotherapy
Negative	Reference		Reference
Positive	0.782 (0.651–0.939)	0.008	0.781 (0.649–0.938)	0.008