Table 1.
Univariate and multivariate Cox proportional hazards regression analysis of survival in the immunotherapy cohort (n = 32).
| Univariate | Bootstrap Results (1000 Replicas) | Multivariate 1 | Bootstrap Results (1000 Replicas) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Variable | Groups. | HR (95% CI) | p | Bias | SE | 95% CI | p | HR (95% CI) | p | Bias | SE | 95% CI | p |
| Total EVs | ≤14,360 EVs/μL vs. >14,360 EVs/μL2 | 0.45 (0.17–1.14) | 0.09 | −0.003 | 0.43 | −1.70 to 0.01 | 0.04 | ||||||
| Leukocyte-EVs | ≤169 EVs/μL vs.>169 EVs/μL 2 | 1.19 (0.26–2.01) | 0.76 | −0.01 3 | 0.72 3 | −1.18 to 1.37 3 | 0.72 3 | ||||||
| Endothelial-EVs | ≤94 EVs/μL vs. >94 EVs/μL 2 | 0.13 (0.04–0.50) | 0.003 | −0.19 | 0.91 | −4.77 to −0.87 | 0.004 | 0.16 (0.04–0.63) | 0.008 | −0.96 | 3.10 | −13.4 to −0.65 | 0.005 |
| Age | ≥65 vs. <65 | 1.24 (0.49–3.10) | 0.65 | 0.06 | 0.47 | −0.64 to 1.26 | 0.61 | ||||||
| No. metastatic sites | ≥2 vs. <2 | 2.86 (1.02–8.04) | 0.04 | 0.11 | 0.57 | 0.21 to 2.42 | 0.02 | 2.67 (0.73–9.70) | 0.13 | 0.58 | 2.30 | 0.08 to 12.3 | 0.04 |
| ECOG PS | 1–2 vs. 0 | 2.77 (0.90–8.54) | 0.08 | 0.14 | 0.64 | 0.19 to 2.66 | 0.02 | ||||||
| Tissue PD-L1 | ≥1% vs. <1% | 0.77 (0.42–1.45) | 0.43 | −0.13 | 0.48 | −1.67 to 0.30 | 0.45 | ||||||
| Line of therapy | 2nd/3rd line vs. 1st line | 1.18 (0.55–2.56) | 0.66 | −0.007 | 0.40 | −0.70 to 0.97 | 0.40 | ||||||
1 Variables with p < 0.05 in the univariate analysis were included in the multivariate analysis. 2 Optimal cut-off values derived from ROC curves. 3 Based on 999 samples Abbreviations: HR: Hazard ratio; SE: standard error; CI: confidence interval.