Table 1.
Patients’ characteristics in the training and validation group
| Characteristics | Overall (n = 108) | Training (n = 74) | Validation (n = 34) | p value |
|---|---|---|---|---|
| Counts (%)/mean (range) | Counts (%)/mean (range) | Counts (%)/mean (range) | ||
| Gender | 1.00 | |||
| Male | 88 (81.5) | 60 (81.1) | 28 (82.3) | |
| Female | 20 (18.5) | 14 (18.9) | 6 (17.7) | |
| Clinical stage | 0.20 | |||
| I | 50 (46.3) | 35 (47.3) | 15 (44.2) | |
| II | 12 (11.1) | 5 (6.8) | 7 (20.6) | |
| III | 16 (14.8) | 12 (16.2) | 4 (11.8) | |
| IV | 30 (27.8) | 22 (29.7) | 8 (23.4) | |
| Histology | 0.42 | |||
| Adenocarcinoma | 51 (47.2) | 35 (47.3) | 16 (47.1) | |
| SCC | 34 (31.5) | 21 (28.4) | 13 (38.2) | |
| Unknown | 23 (21.3) | 18 (24.3) | 5 (14.7) | |
| GTV volume (cc) | 46.6 (359.5) | 45.6 (319.8) | 48.7 (359.5) | 0.83 |
| PTV volume (cc) | 112.6 (578.6) | 113.5 (578.6) | 110.6 (514.7) | 0.91 |
| MD (cm) | 4.6 (9.4) | 4.5 (9.3) | 4.8 (9.2) | 0.52 |
| ED (cm) | 3.7 (8.4) | 3.7 (7.4) | 3.8 (8.4) | 0.87 |
| LCR (%) | 26.2 (84.6) | 25.8 (84.6) | 26.9 (44.3) | 0.59 |
| BEDPTVmax (Gy10) | 51.2 (59.7) | 51.4 (57.4) | 50.9 (56.8) | 0.86 |
| Fractional dose (Gy) | 10.4 (22.0) | 10.3 (22.0) | 10.6 (21.0) | 0.78 |
| Duration (days) | 9.7 (37.0) | 10.2 (29.0) | 8.8 (37.0) | 0.54 |
| 3-Year CSS | 0.95 | |||
| Yes | 44 (40.7) | 30 (40.5) | 14 (41.2) | |
| No | 64 (59.3) | 44 (59.5) | 20 (58.8) |
SCC squamous cell carcinoma, GTV gross target volume, PTV planning target volume, MD maximum diameter for the tumor, ED equivalent diameter for the tumor, LCR lymphocyte ratio, BEDPTVmax the maximum dose in PTV recorded as BED, CSS cancer-specific survival