Table 3.
Performance of the AI signature in the validation sets*
| Analysis | Anti-EGFR treatment |
No anti-EGFR treatment |
||
|---|---|---|---|---|
| FOLFIRI + cetuximab |
FOLFIRI only |
|||
| mCRC |
mCRC |
|||
| CRC-FCHQ | CRC-FCSD | CRC-FHQ | CRC-FSD | |
| Reference standard | OS | OS | OS | OS |
| No. patients | ||||
| Total | 116 | 186 | 129 | 236 |
| Training | 78 | 124 | 78 | 159 |
| Sensitive | 48 | 71 | 42 | 85 |
| Resistant | 30 | 53 | 36 | 74 |
| Validation | 38 | 62 | 51 | 78 |
| Sensitive | 23 | 34 | 32 | 42 |
| Resistant | 15 | 28 | 19 | 36 |
| Signature | ||||
| Algorithm | Random Forest | Random Forest | Random Forest | Random Forest |
| Features | Shape SI4 | Shape SI4 | Shape SI4 | Shape SI4 |
| LoG Z Entropy | LoG Z Entropy | LoG Z Entropy | LoG Z Entropy | |
| GTDM Contrast | GTDM Contrast | GTDM Contrast | GTDM Contrast | |
| LoG X Entropy | LoG X Entropy | LoG X Entropy | LoG X Entropy | |
| Performance | ||||
| Tumor sensitivity | OS >17.7 mo | OS >17.7 mo | OS >17.7 mo | OS >17.7 mo |
| AUC, training | 0.83 (95% CI = 0.75 to 0.95) | 0.84 (95% CI = 0.76 to 0.89) | 0.75 (95% CI = 0.63 to 0.85) | 0.75 (95% CI = 0.67 to 0.82) |
| AUC, validation | 0.80 (95% CI = 0.69 to 0.94) | 0.72 (95% CI = 0.59 to 0.83) | 0.59 (95% CI = 0.44 to 0.72) | 0.55 (95% CI = 0.43 to 0.66) |
| Association with OS | ||||
| Cox regression | ||||
| Hazard ratio | 44.3 (95% CI = 6.4 to 307.7) | 6.5 (95% CI = 1.8 to 23.6) | 1.9 (95% CI = 0.4 to 8.4) | 0.96 (95% CI = 0.2 to 4.3) |
| Death | 31/38 | 53/62 | 42/51 | 69/78 |
| P | .0001 | .005 | .43 | .96 |
*
The performance of the AI signature to detect treatment sensitivity was evaluated in all cohorts. AI = Artificial Intelligence; AUC = Area Under the Curve; CT = computed tomography; CRC = colorectal cancer; F = FOLFIRI; FC = FOLFIRI+cetuximab; HQ = High computed tomography quality; SD = Standard computed tomography quality.