Perioperative risk factors for prognosis in patients undergoing radical esophagectomy: A retrospective study

Table 7 Multivariate analysis of survival-related factors in radically resected esophageal squamous cell carcinoma, n (%)

Variables	Hazard ratio	95%CI	P value
TNM staging	-	-	-
Phase I and II	1.00	Reference	-
Phase III and IV	2.31	1.72-3.10	< 0.001
Degree of tumor differentiation	-	-	-
Well differentiated	1.00	Reference	-
Moderately differentiated	1.46	1.02-2.09	0.038
Poorly differentiated	2.15	1.47-3.14	< 0.001
Postoperative analgesics used for more than 5 days	-	-	-
≤ 5 days	1.00	Reference	-
> 5 days	1.43	1.08-1.89	0.012

CI: Confidence interval; TNM: Tumor-node-metastasis.