Table 1 Baseline demographics of patients with first and second primary lung cancer
1st primary (N = 1075) | 2nd primary (N = 1075) | |
|---|---|---|
Age (mean, y) | 68.8 (9.0) | 70.6 (9.0) |
Histology | ||
Adenocarcinoma | 649 (60.4%) | 576 (53.6%) |
Squamous cell | 245 (22.8%) | 196 (18.2%) |
Other | 181 (16.8%) | 303 (28.2%) |
Tumor size (mean, mm) | 18.7 (6.4) | 15.4 (6.3) |
Tumor site | ||
Upper | 680 (63.3%) | 625 (58.1%) |
Middle | 50 (4.6%) | 61 (5.7%) |
Lower | 332 (30.9%) | 377 (35.1%) |
Not determined | 13 (1.2%) | 12 (1.1%) |
Grade | ||
Well | 195 (18.1%) | 213 (19.8%) |
Moderately | 402 (37.4%) | 327 (30.4%) |
Poorly or undifferentiated | 301 (28.0%) | 189 (17.6%) |
Not determined | 177 (16.5%) | 346 (32.2%) |
SEER stage | ||
In situ | 5 (0.5%) | 0 (0.0%) |
Localized | 1070 (99.5%) | 1075 (100.0%) |
– | – | – |
Types of surgery | ||
Lobectomy | 538 (50.1%) | 236 (22.0%) |
Sublobectomy | 311 (28.9%) | 395 (36.7%) |
No surgery | 226 (21.0%) | 444 (41.3%) |