Table 4.
Quantitative results of esophageal GTV segmentation by the pCT model in the multi-institutional external testing data.
| Institutions 2–4 (External Multi-Institutional Testing) Using pCT Model | ||||
|---|---|---|---|---|
| Unacceptable Number (percentage) | DSC Mean (95% CI) | HD95 (mm) Mean (95% CI) | ASD (mm) Mean (95% CI) | |
| Total patients (n = 354) | 33 (9%) | 0.80 (0.78, 0.81) | 11.8 (10.1, 13.4) | 2.8 (2.4, 3.2) |
| Clinical T stage | ||||
| cT2 (n = 74) | 23 (31%) | 0.71 (0.66, 0.76) | 13.8 (10.0, 17.5) | 3.6 (2.5, 4.8) |
| cT3 (n = 177) | 5 (3%) | 0.81 (0.80, 0.82) | 11.4 (8.8, 13.9) | 2.6 (2.1, 3.2) |
| cT4 (n = 103) | 5 (5%) | 0.82 (0.80, 0.83) | 11.4 (9.3, 13.6) | 2.7 (2.1, 3.3) |
| Tumor location | ||||
| Cervical (n = 60) | 4 (6%) | 0.80 (0.78, 0.82) | 11.7 (8.6, 14.8) | 2.5 (1.7, 3.3) |
| Upper third (n = 143) | 11 (8%) | 0.79 (0.77, 0.81) | 12.6 (10.4, 14.9) | 3.0 (2.4, 3.7) |
| Middle third (n = 178) | 14 (8%) | 0.80 (0.78, 0.81) | 11.5 (9.3, 13.5) | 2.9 (2.4, 3.5) |
| Lower third (n = 70) | 5 (7%) | 0.80 (0.78, 0.82) | 15.4 (9.3, 21.5) | 3.3 (2.1, 4.5) |
GTV, gross tumor volume; CI, confidence interval; DSC, Dice similarity coefficient; HD95, 95% Hausdorff distance; ASD, average surface distance; cT2, clinical T stage 2; cT3, clinical T stage 3; cT4, clinical T stage 4; pCT, treatment planning CT.