1. Clinical characteristics of study patients (N=46).
| Characteristics | n (%) |
| Age (year) | |
| 70−79 | 31 (67.4) |
| 80−90 | 15 (32.6) |
| Gender | |
| Male | 33 (71.7) |
| Female | 13 (28.3) |
| Karnofsky performance score | |
| 70−80 | 6 (13.0) |
| 90−100 | 40 (87.0) |
| Weight loss (last 6 months) | |
| <5% | 30 (65.2) |
| ≥5% | 16 (34.8) |
| Histology | |
| Adenocarcinoma | 1 (2.2) |
| Squamous cell carcinoma | 45 (97.8) |
| Primary tumor location | |
| Upper thoracic segment | 13 (28.3) |
| Middle thoracic segment | 23 (50.0) |
| Lower thoracic segment | 10 (21.7) |
| T stage | |
| T1 | 1 (2.2) |
| T2 | 3 (6.5) |
| T3 | 25 (54.3) |
| T4 | 17 (37.0) |
| N stage | |
| N0 | 9 (19.6) |
| N1 | 37 (80.4) |
| M stage | |
| M0 | 38 (82.6) |
| M1a | 8 (17.4) |
| Clinical stage | |
| I | 10 (21.7) |
| II | 28 (60.9) |
| III | 8 (17.4) |
| Length of primary tumor (cm) | |
| <5 | 12 (26.1) |
| ≥5 | 34 (73.9) |
| Charlson score | |
| 0 (group A) | 34 (73.9) |
| ≥1 (group B) | 12 (26.1) |
| Dysphagia grade | |
| Normal | 9 (19.6) |
| Soft | 15 (32.6) |
| Semifluid | 9 (19.6) |
| Fluid | 13 (28.3) |