Table 1.

Univariate and multivariable Cox regression analyses of the association cfDNA plasma concentrations (ng/mL) with patient outcome including established prognostic factors.

rPFSOS
Univariate analysesNHR (95% CI)PHR (95% CI)P
4 weeks
 CTC conversion470.30 (0.14–0.65)0.0020.53 (0.27–1.04)0.07
 ≥30% CTC decline470.33 (0.15–0.74)0.0070.86 (0.42–1.74)0.67
 cfDNA [c] log-fold change461.70 (1.13–2.55)0.011.30 (0.87–1.95)0.19
 ≥30% cfDNA [c] decline460.61 (0.33–1.14)0.120.70 (0.37–1.32)0.27
 ≥50% cfDNA [c] decline460.41 (0.21–0.80)0.0090.74 (0.40–1.37)0.34
8 weeks
 CTC conversion410.38 (0.19–0.74)0.005a0.74 (0.39–1.42)0.37a
 ≥30% CTC decline410.61 (0.31–1.19)0.151.21 (0.62–2.37)0.58
 cfDNA [c] log-fold change421.83 (1.22–2.74)0.0031.43 (0.98–2.09)0.06
 ≥30% cfDNA [c] decline420.48 (0.25–0.92)0.0280.66 (0.34–1.26)0.20
 ≥50% cfDNA [c] decline420.24 (0.11–0.52)0.00010.34 (0.16–0.73)0.006
Multivariate analysesHR (95% CI)PHR (95% CI)P
4 weeks
 LDH1.00 (1.00–1.00)0.0581.00 (1.00–1.00)0.012
 ECOG status 2 (vs. 0–1)1.48 (0.50–4.38)0.481.74 (0.60–5.06)0.31
Radiological progression at trial entry (vs. PSA progression only)1.01 (0.42–2.43)0.980.20 (0.07–0.52)0.001
 Measurable disease at trial entry0.32 (0.13–0.79)0.0140.50 (0.20–1.29)0.154
 Baseline CTC1.00 (0.99–1.00)0.201.00 (1.00–1.00)0.34
 Baseline cfDNA1.00 (1.00–1.01)0.541.00 (1.00–1.01)0.23
 CTC conversion0.19 (0.07–0.05)0.0010.41 (0.17–1.01)0.051
 ≥50% cfDNA [c] decline0.25 (0.09–0.66)0.0050.44 (0.18–1.07)0.071
8 weeks
 LDH1.00 (1.00–1.01)0.0361.00 (1.00–1.01)<0.001
 ECOG status 2 (vs. 0–1)2.45 (0.73–8.24)0.152.55 (0.81–7.98)0.11
Radiologic progression at trial entry (vs. PSA progression only)1.37 (0.47–4.00)0.570.24 (0.08–0.72)0.011
 Measurable disease at trial entry0.49 (0.18–1.31)0.150.53 (0.19–1.50)0.24
 Baseline CTC1.00 (1.00–1.00)0.831.00 (0.99–1.00)0.24
 Baseline cfDNA1.00 (0.99–1.00)0.321.00 (0.99–1.01)0.89
 CTC conversion0.10 (0.03–0.28)<0.0010.35 (0.15–0.85)0.020
 ≥50% cfDNA [c] decline0.09 (0.03–0.30)<0.0010.19 (0.06–0.56)0.003
  • Abbreviations: ECOG, Eastern Cooperative Oncology Group; LDH, lactate dehydrogenase.

  • aIndicates when proportional hazards assumption is not met.