Efficacy and safety of immune checkpoint inhibitors plus chemotherapy in esophageal cancer patients with liver metastases

Table 5 Results of univariate Cox regression analysis

Influential factors (independent variables)	P value	HR	95%CI for HR
			Lower bound	Upper bound
Age (> 60/≤ 60 years)	0.537	1.124	0.775	1.630
Sex (male/female)	0.781	1.124	0.493	2.560
Underlying diseases (yes/no)	0.324	1.220	0.822	1.810
Dysphagia or cancer-related symptoms (yes/no)	0.217	0.737	0.454	1.196
KPS score (≥ 70/< 70)	0.013a	6.117	1.463	25.573
Histology
ESCC, dummy variable	0.164
EAC	0.163	1.563	0.835	2.928
Other	0.168	2.269	0.709	7.267
Tumor location
Upper, dummy variable	0.819
Middle	0.595	1.317	0.478	3.628
Lower	0.798	0.952	0.652	1.390
Tumor differentiation grade
Grade 1, dummy variable	0.298
Grade 2	0.140	2.044	0.791	5.281
Grade 3-4	0.121	2.110	0.821	5.427
Tumor stage (T1-2/T3-4)	0.121	1.539	0.892	2.656
Nodal stage (N0/N+)	0.758	1.092	0.623	1.915
Synchronous liver metastasis at initial diagnosis (yes/no)	0.795	1.050	0.726	1.519
Distant lymph node metastasis (yes/no)	0.036a	1.492	1.027	2.168
Primary lesion surgery (yes/no)	0.080	0.712	0.488	1.041
Primary lesion radiotherapy (yes/no)	0.765	0.944	0.649	1.373
Pre-hepatic metastasis chemotherapy (yes/no)	0.441	0.854	0.571	1.277
Pre-hepatic metastasis targeted therapy (yes/no)	0.009a	4.809	1.477	15.656
Child-Pugh score (> 6/≤ 6)	0.107	3.224	0.778	13.361
Number of liver metastases (> 3/≤ 3)	0.012a	1.650	1.115	2.441
oligometastatic liver disease (yes/no)	0.001a	0.434	0.261	0.725
Hepatic lobe involvement
Bilateral lobes, dummy variable	0.024a
Left lobe	0.070	0.462	0.200	1.066
Right lobe	0.021a	0.616	0.409	0.929
Extrahepatic metastasis (yes/no)	0.334	1.201	0.828	1.743
Lung metastasis (yes/no)	0.614	1.118	0.724	1.728
Bone metastasis (yes/no)	0.299	1.300	0.792	2.135
Brain metastasis (yes/no)	0.161	0.366	0.090	1.491
Chemotherapy regimen
Taxane-based ± platinum, dummy variable	0.012a
Fluoropyrimidine ± platinum	0.627	1.115	0.720	1.727
Other	0.003a	2.231	1.313	3.792
Chemotherapy cycle (≥ 4/< 4)	< 0.001a	0.261	0.160	0.425
Immunotherapy (yes/no)	0.005a	0.551	0.364	0.836
Immunotherapy cycle (≥ 4/< 4)	0.004a	0.538	0.353	0.820
Liver local treatment (yes/no)	0.005a	0.546	0.358	0.833
Local treatment modalities
None, dummy variable	0.047a
Ablation	0.027a	0.565	0.340	0.937
Surgery	0.217	0.528	0.192	1.455
TACE	0.409	1.530	0.557	4.203
Radiotherapy	0.064	0.424	0.171	1.050

^aP < 0.05, statistical significance included in multifactor Cox regression analysis.

HR: Hazard ratio; 95%CI: 95% confidence interval; TACE: Transarterial chemoembolization; KPS: Karnofsky Performance Status; ESCC: Esophageal squamous cell carcinoma; EAC: Esophageal adenocarcinoma.