Table 1.
Baseline Characteristics of Patients with N2 Non-small Cell Lung Cancer According to Postoperative Radiation Therapy Treatment
| Characteristic | PORT1 N=710 |
No PORT N=597 |
P-value | |
|---|---|---|---|---|
| Unadjusted | Adjusted2 | |||
| Age, years, n (%) | <0.0001 | 0.96 | ||
| ≤70 | 297 (42) | 177 (30) | ||
| 71–75 | 241 (34) | 196 (33) | ||
| >75 | 172 (24) | 224 (38) | ||
| Female, n (%) | 371 (52) | 279 (47) | 0.04 | 0.99 |
| Race, n (%) | ||||
| White | 612 (85) | 518 (87) | 0.77 | 0.89 |
| African-American | 46 (7) | 37 (6) | ||
| Hispanic | 18 (3) | 15 (3) | ||
| Other | 34 (5) | 27 (4) | ||
| Median Income in ZIP Code of Residence, n (%) | ||||
| Lowest quartile | 134 (19) | 145 (24) | 0.03 | 0.94 |
| Second quartile | 182 (26) | 155 (26) | ||
| Third quartile | 187 (26) | 124 (21) | ||
| Highest quartile | 204 (29) | 172 (29) | ||
| Charlson Comorbidity Score, n (%) | ||||
| ≤1 | 324 (46) | 245 (41) | 0.14 | 0.98 |
| 1–2 | 223 (31) | 190 (31) | ||
| >2 | 163 (23) | 162 (27) | ||
| Tumor Status, n (%) | ||||
| T1 | 172 (24) | 148 (25) | 0.98 | 0.99 |
| T2 | 419 (59) | 348 (58) | ||
| T3 | 119 (17) | 101 (17) | ||
| Number of Lymph Nodes Evaluated, n (%) | ||||
| ≤5 | 170 (24) | 126 (21) | 0.19 | 0.70 |
| 6–9 | 163 (23) | 124 (21) | ||
| ≥10 | 377 (53) | 347 (58) | ||
| Number of Positive Lymph Nodes, n (%) | ||||
| ≤2 | 311 (44) | 300 (50) | 0.05 | 0.89 |
| 3–4 | 156 (22) | 108 (18) | ||
| ≥5 | 243 (34) | 189 (32) | ||
| Histology, n (%) | ||||
| Adenocarcinoma | 455 (64) | 379 (63) | 0.71 | 0.98 |
| Squamous cell carcinoma | 199 (28) | 167 (28) | ||
| Large cell carcinoma | 38 (5) | 31 (5) | ||
| Other | 18 (3) | 20 (3) | ||
| Type of Surgery, n (%) | 0.11 | 0.98 | ||
| Lobectomy | 623 (88) | 506 (85) | ||
| Pneumonectomy | 87 (12) | 91 (15) | ||
| Adjuvant Chemotherapy, n (%) | ||||
| None | 455 (64) | 461 (77) | <0.0001 | 0.0023 |
| Platinum-based | 223 (31) | 118 (20) | ||
| Other Chemotherapy | 32 (5) | 18 (3) | ||
1
PORT denotes postoperative radiotherapy.
2
P-values adjusting for propensity scores.
3
Variable not included in the propensity score model as chemotherapy is used in most cases concomitantly with radiation.