Table 4. Subgroup meta-analyses of overall and disease-/progression-free survival.
| Subgroups | OS | DFS/PFS | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HR | 95% CI | I2 (%) | P value | No. of studies | Subgroup heterogeneity P value (I2) | HR | 95% CI | I2 (%) | P value | No. of studies | Subgroup heterogeneity P value (I2) |
|
| Total | 1.84 | 1.37–2.45 | 47 | < 0.0001 | 12 | - | 1.93 | 1.19–3.11 | 54 | 0.007 | 4 | - |
| Sampling site | 0.86 (0%) | 0.57 (0%) | ||||||||||
| PB | 2.03 | 1.14–3.63 | 65 | 0.02 | 6 | 1.95 | 0.97–3.92 | 67 | 0.06 | 3 | ||
| BM | 1.91 | 1.36–2.68 | 0 | 0.0002 | 5 | 2.46 | 1.63–3.71 | - | < 0.0001 | 1 | ||
| Detection method | 0.03 (70.9%) | 0.24 (30.5%) | ||||||||||
| CellSearch | 2.79 | 1.39–5.63 | 71 | 0.004 | 3 | 1.34 | 0.94–1.90 | - | 0.11 | 1 | ||
| RT-PCR | 1.25 | 0.96–1.62 | 0 | 0.09 | 4 | 2.67 | 1.11–6.39 | 47 | 0.03 | 2 | ||
| ID | 1.91 | 1.36–2.68 | 0 | 0.0002 | 5 | 2.05 | 1.08–3.94 | - | 0.03 | 1 | ||
| Treatment intent | 0.11 (55.6%) | 0.15 (51.6%) | ||||||||||
| Potentially curable | 0.94 | 0.52–1.70 | - | 0.84 | 1 | - | - | - | - | - | ||
| Palliative | 2.25 | 1.06–4.77 | 74 | 0.04 | 2 | 1.34 | 0.94–1.90 | - | 0.11 | 1 | ||
| Both | 1.80 | 1.35–2.42 | 22 | <0.0001 | 9 | 2.67 | 1.11–6.39 | 47 | 0.03 | 2 | ||
| Location of study | 0.51 (0%) | - | ||||||||||
| European | 1.70 | 1.30–2.22 | 39 | 0.0001 | 10 | 1.93 | 1.19–3.11 | 54 | 0.007 | 4 | ||
| Non-European | 3.02 | 0.57–16.11 | 46 | 0.20 | 2 | - | - | - | - | - | ||
| Risk of bias | 0.98 (0%) | - | ||||||||||
| Low | 1.93 | 1.43–2.59 | 46 | < 0.0001 | 9 | 1.93 | 1.19–3.11 | 54 | 0.007 | 4 | ||
| High | 1.97 | 0.49–7.92 | 51 | 0.34 | 3 | - | - | - | - | - | ||
| CTC/DTC positive | 0.01 (84.6%) | 0.84 (0%) | ||||||||||
| ≥ 35 % of patients | 1.51 | 1.15–1.99 | 31 | 0.003 | 8 | 2.16 | 0.75–6.19 | 84 | 0.15 | 2 | ||
| < 35 % of patients | 2.86 | 1.91–4.28 | 0 | < 0.00001 | 4 | 1.91 | 1.11–3.30 | 0 | 0.02 | 2 | ||