Table 1. Clinical and demographic variables in the prospective (n=201) and retrospective (n=301) patient groups.
| Variable | No. of Patients (%), Prospective Group | HR (95% CI) | P Value* | No. of Patients (%), Retrospective Group | P Value† |
|---|---|---|---|---|---|
| Age | |||||
| >70 | 62 (30.8) | 0.73 (0.44–1.22) | 0.227 | 106 (35.2) | 0.309 |
| <70 | 139 (69.2) | 195 (64.8) | |||
| Sex | |||||
| Female | 88 (43.8) | 0.84 (0.55–1.29) | 0.428 | 126 (41.9) | 0.670 |
| Male | 113 (56.2) | 175 (58.1) | |||
| Smoker | |||||
| Yes | 183 (91.0) | 0.83 (0.42–1.66) | 0.603 | 272 (90.4) | 0.798 |
| No | 18 (9.0) | 29 (9.6) | |||
| Alcohol Use | |||||
| Yes | 98 (48.8) | 1.17 (0.77–1.79) | 0.462 | 109 (36.3) | 0.005 |
| No | 103 (51.2) | 192 (63.7) | |||
| Diabetes | |||||
| Yes | 36 (17.9) | 0.89 (0.48–1.64) | 0.708 | 39 (13.2) | 0.127 |
| No | 165 (82.1) | 262 (86.8) | |||
| Heart Disease | |||||
| Yes | 91 (45.3) | 1.32 (0.86–2.01) | 0.202 | 182 (60.5) | 0.001 |
| No | 110 (54.7) | 119 (39.5) | |||
| Disease Stage | |||||
| I-II | 15 (7.5) | 33 (11.0) | |||
| III-IV | 174 (86.6) | 0.86 (0.60–1.23) | 0.414 | 248 (82.4) | 0.391 |
| Recurrence | 12 (6.0) | 20 (6.6) | |||
| Tumor Histology | |||||
| Non-Adeno | 95 (47.3) | 0.92 (0.66–1.28) | 0.628 | 184 (61.1) | 0.062 |
| Adenocarcinoma | 106 (52.7) | 117 (38.9) | |||
| Tumor Location | |||||
| Left | 76 (37.8) | 117 (38.9) | |||
| Right | 125 (62.2) | 0.66 (0.43–1.02) | 0.058 | 169 (56.1) | 0.005 |
| Other | 15 (5.0) | ||||
| RT Modality | |||||
| Proton | 75 (37.3) | 0.92 (0.59–1.44) | 0.704 | 128 (42.5) | 0.244 |
| Photon (IMRT) | 126 (62.7) | 173 (57.5) | |||
| Chemotherapy | |||||
| Induction | 66 (32.8) | 0.99 (0.63-1.55) | 0.952 | 95 (31.6) | 0.764 |
| Concurrent | 199 (99.0) | 20 (0.001–7×105) | 0.575 | 255 (84.7) | <0.001 |
| Adjuvant | 36 (17.9) | 2.18 (1.36–3.49) | 0.001 | 63 (20.9) | 0.405 |
Abbreviations: HR, hazard ratio; CI, confidence interval; RT, radiation therapy; IMRT, intensity-modulated radiation therapy.
*
Cox proportional hazards for univariate analysis of associations with PCE development
†
Chi-squared test to assess differences in categorical variables between the two patient groups