Table 2.

Univariate and multivariate analyses of factors associated with 5-year OS and 5-year DFS

Variables	5-year OS			5-year DFS
	Univariate	Multivariate	P	Univariate	Multivariate	P
	P	HR (95% CI)		P	HR (95% CI)
Age	0.024	1.026 (1.005–1.047)	0.014	0.011	0.979 (0.959–0.999)	0.039
Sex (male)	0.369			0.066
BMI (kg/m2)	0.307			0.326
CEA	< 0.001	1.016 (1.007–1.026)	0.001	0.058
ASA class	0.053		0.669	0.032
Tumour location	0.036		0.054	0.001	0.872 (0.802–0.948)	0.001
With robotic surgery	0.925			0.451
With previous abdominal surgery	0.065			0.583
Lymph nodes retrieved	0.332			0.036	0.937 (0.888–0.989)	0.018
TNM stage	0.003	1.622 (1.068–2.464)	0.023	0.001	1.919 (1.241–2.969)	0.003
Differentiation grade	0.010	1.664 (1.093–2.535)	0.018	< 0.001	1.660 (1.116–2.469)	0.012
CRM (no involved)	0.302			0.754
With lymphovascular invasion	0.018		0.123	0.005

Statistical analysis was performed using a multivariable Cox proportional hazards model. Significant variables from the univariate analysis were included in the multivariate Cox regression models to assess their contribution to 5-year OS and DFS. Variables with a P < 0.05 and hazard ratio (HR) > 20% were kept in the final model

Bold values indicate statistical significance

BMI body mass index, ASA American Society of Anesthesiologists, CRT chemoradiotherapy, TNM tumour node metastasis, CRM circumferential resection margin, OS overall survival, DFS disease-free survival, HR Hazard radio, 95% CI 95% confidence interval