Table 2.
Pretreatment and treatment characteristics for propensity score-matched patients per elective nodal irradiation status.
| Covariate | All patients (N = 646) | ENI (N = 323) | IFRT (N = 323) | P value |
|---|---|---|---|---|
| Median age, y (range) | 63 (31–79) | 63 (31–79) | 64 (34–78) | 0.92 |
|
| ||||
| Age group, y (%) | ||||
| ≤70 years | 586 (90.7) | 294 (91.0) | 292 (90.4) | 0.86 |
| 70 years | 60 (9.3) | 29 (9.0) | 31 (9.6) | |
|
| ||||
| Gender (%) | ||||
| Male | 400 (61.9) | 201 (62.2) | 199 (61.6) | 0.81 |
| Female | 246 (38.1) | 122 (37.8) | 124 (38.4) | |
|
| ||||
| KPS (%) | ||||
| 90–100 | 461 (71.4) | 232 (71.8) | 229 (70.9) | 0.74 |
| 70–80 | 185 (28.6) | 91 (28.2) | 94 (29.1) | |
|
| ||||
| Histology (%) | ||||
| AC | 348 (53.9) | 177 (54.8) | 171 (52.9) | 0.62 |
| SCC | 298 (46.1) | 146 (45.2) | 152 (47.1) | |
|
| ||||
| T-stage | ||||
| 1-2 | 289 (44.8) | 143 (44.3) | 146 (45.2) | 0.43 |
| 3-4 | 357 (55.2) | 180 (55.7) | 177 (54.8) | |
|
| ||||
| N-stage | ||||
| 2 | 325 (50.3) | 164 (50.8) | 161 (49.8) | 0.79 |
| 3 | 321 (49.7) | 159 (49.2) | 162 (50.2) | |
|
| ||||
| Disease stage (%) | ||||
| IIIB | 385 (59.6) | 195 (60.4) | 190 (58.8) | 0.57 |
| IIIC | 261 (40.4) | 128 (39.6) | 133 (41.2) | |
|
| ||||
| Chemotherapy cycles (%) | ||||
| 2-3 | 529 (81.9) | 263 (81.4) | 266 (82.3) | 0.71 |
| 1 | 117 (18.1) | 60 (18.6) | 57 (17.7) | |
|
| ||||
| Radiotherapy technique (%) | ||||
| 3D-CRT | 248 (38.4) | 127 (39.3) | 121 (37.5) | 0.69 |
| IMRT | 398 (61.6) | 196 (60.7) | 202 (62.5) | |
ENI: elective nodal irradiation; IFRT: involved-field radiotherapy; KPS: Karnofsky performance score; AC: adenocarcinoma; SCC: squamous cell cancer; T: tumor; N: node; 3D-CRT: 3-dimensional conformal radiotherapy; IMRT: intensity-modulated radiotherapy.