Table 4.
Training and validation of multivariate Cox models for the endpoint loco-regional control containing cancer stem cell marker expression and hypoxia classifiers in addition to HPV16 DNA status and the clinical parameters ECE status, localisation oropharynx and hypopharynx. Shown is the concordance index (ci) with 95% confidence interval (CI) and the p-value testing the hypothesis ci = 0.5. Validation was also performed for the subgroup of patients who received radiochemotherapy (RCT).
| Training cohort |
Validation cohort |
Validation cohort, RCT only |
||||
|---|---|---|---|---|---|---|
| Included variables | ci (95% CI) | p-Value | ci (95% CI) | p-Value | ci (95% CI) | p-Value |
| All patients | ||||||
| Baseline (clinical parameters, HPV16 DNA status) | 0.76 (0.67–0.83) | <0.01 | 0.66 (0.58–0.75) | <0.01 | 0.69 (0.40–0.91) | 0.15 |
| CD44 > 0.2 | 0.76 (0.68–0.83) | <0.01 | 0.69 (0.60–0.77) | <0.01 | 0.77 (0.55–0.93) | 0.02 |
| SLC3A2 > −3.135 | 0.77 (0.68–0.84) | <0.01 | 0.66 (0.56–0.76) | <0.01 | 0.72 (0.44–0.92) | 0.10 |
| MET > −4.135 | 0.78 (0.69–0.85) | <0.01 | 0.64 (0.54–0.74) | 0.01 | 0.75 (0.50–0.92) | 0.04 |
| 15-gene signature | 0.80 (0.73–0.87) | <0.01 | 0.68 (0.58–0.77) | <0.01 | 0.74 (0.44–0.93) | 0.10 |
| 26-gene signature | 0.79 (0.71–0.85) | <0.01 | 0.67 (0.58–0.75) | <0.01 | 0.71 (0.43–0.91) | 0.11 |
| CD44 > 0.2, 15-gene signature | 0.80 (0.72–0.87) | <0.01 | 0.69 (0.60–0.78) | <0.01 | 0.78 (0.53–0.94) | 0.04 |
| SLC3A2 > −3.135, 15-gene signature | 0.81 (0.73–0.87) | <0.01 | 0.67 (0.58–0.75) | <0.01 | 0.76 (0.48–0.95) | 0.07 |
| MET > −4.135, 15-gene signature | 0.81 (0.74–0.88) | <0.01 | 0.66 (0.56–0.75) | <0.01 | 0.75 (0.47–0.93) | 0.07 |
| Patients with HPV16 DNA negative tumours | ||||||
| Baseline (clinical parameters) | 0.66 (0.55–0.77) | 0.01 | 0.63 (0.54–0.71) | 0.01 | 0.60 (0.21–0.87) | 0.49 |
| CD44 > 0.2 | 0.68 (0.58–0.77) | <0.01 | 0.63 (0.53–0.73) | 0.01 | 0.70 (0.41–0.90) | 0.13 |
| SLC3A2 > −3.135 | 0.69 (0.58–0.79) | <0.01 | 0.62 (0.51–0.71) | 0.03 | 0.63 (0.26–0.89) | 0.38 |
| MET > −4.135 | 0.71 (0.60–0.81) | <0.01 | 0.58 (0.47–0.70) | 0.16 | 0.66 (0.31–0.90) | 0.25 |
| 15-gene signature | 0.74 (0.65–0.82) | <0.01 | 0.64 (0.54–0.74) | 0.01 | 0.64 (0.25–0.91) | 0.36 |
| 26-gene signature | 0.71 (0.62–0.80) | <0.01 | 0.62 (0.53–0.71) | 0.01 | 0.61 (0.26–0.88) | 0.42 |
| CD44 > 0.2, 15-gene signature | 0.74 (0.65–0.82) | <0.01 | 0.65 (0.54–0.74) | 0.01 | 0.69 (0.36–0.91) | 0.19 |
| SLC3A2 > −3.135, 15-gene signature | 0.76 (0.68–0.84) | <0.01 | 0.62 (0.52–0.72) | 0.03 | 0.68 (0.33–0.92) | 0.24 |
| MET > −4.135, 15-gene signature | 0.76 (0.68–0.84) | <0.01 | 0.61 (0.50–0.71) | 0.05 | 0.66 (0.29–0.91) | 0.29 |