Table 1. Basic characteristics of invasive mucinous and nonmucinous adenocarcinoma at the time of diagnosis.
| Variables | IMA (N=786) | NMA (N=101,065) | P value |
|---|---|---|---|
| Age (years) | 65.97±12.02 | 66.09±10.99 | 0.458 |
| Female sex | 465 (59.2%) | 52,792 (52.2%) | <0.001 |
| Race | 0.868 | ||
| Black | 92 (11.7%) | 11,419 (11.3%) | |
| White | 629 (80.0%) | 80,384 (79.5%) | |
| Others | 64 (8.1%) | 9,063 (9.0%) | |
| Unknown | 1 (0.1%) | 199 (0.2%) | |
| Grade | <0.001 | ||
| Grade I | 427 (54.3%) | 9,549 (9.4%) | |
| Grade II | 101 (12.8%) | 25,548 (25.3%) | |
| Grade III | 17 (2.2%) | 28,672 (28.4%) | |
| Grade IV | 0 (0.0%) | 691 (0.7%) | |
| Unknown | 241 (30.7%) | 36,605 (36.2%) | |
| Laterality | 0.004 | ||
| Left | 309 (39.3%) | 39,419 (39.0%) | |
| Single side, not specified | 1 (0.1%) | 149 (0.1%) | |
| Paired side | 26 (3.3%) | 1,586 (1.6%) | |
| Right | 450 (57.3%) | 59,911 (59.3%) | |
| Location | <0.001 | ||
| Upper | 228 (29.0%) | 57,987 (57.4%) | |
| Middle | 36 (4.6%) | 4,910 (4.9%) | |
| Lower | 442 (56.2%) | 26,966 (26.7%) | |
| Main | 1 (0.1%) | 2,420 (2.4%) | |
| Overlapping lesion | 20 (2.5%) | 1,273 (1.3%) | |
| Unknown | 59 (7.5%) | 7,509 (7.4%) | |
| Operation | <0.001 | ||
| No surgery | 131 (16.7%) | 59,691 (59.1%) | |
| Wedge | 101 (12.8%) | 5,545 (5.5%) | |
| Segmentectomy | 16 (2.0%) | 1,293 (1.3%) | |
| Other sublobar | 8 (1.0%) | 458 (0.5%) | |
| Lobectomy | 514 (65.4%) | 32,542 (32.2%) | |
| Pneumonectomy | 16 (2.0%) | 1,536 (1.5%) | |
| Chemotherapy | 235 (29.9%) | 56,089 (55.5%) | <0.001 |
| Radiation | 71 (9.0%) | 46,355 (45.9%) | <0.001 |
| Combinations | <0.001 | ||
| Chemotherapy | 87 (11.1%) | 19,248 (19.0%) | |
| Chemoradiation | 22 (2.8%) | 25,756 (25.5%) | |
| Radiation | 22 (2.8%) | 14,687 (14.5%) | |
| Surgery only | 518 (65.9%) | 28,750 (28.4%) | |
| Surgery + chemotherapy | 110 (14.0%) | 6,712 (6.6%) | |
| Surgery + radiation | 11 (1.4%) | 1,539 (1.5%) | |
| Trimodality | 16 (2.0%) | 4,373 (4.3%) | |
| Tumor diameter (mm) | 53.33±124.49 | 38.35±53.87 | 0.070 |
| Number of lymph nodes positive | 0.19±0.86 | 0.85±2.09 | <0.001 |
| Number of lymph nodes resected | 6.05±7.85 | 3.49±6.44 | <0.001 |
| SPN* | <0.001 | ||
| No data | 440 (66.6%) | 41,728 (47.7%) | |
| None | 161 (24.4%) | 33,921 (38.8%) | |
| SPN | 60 (9.1%) | 11,766 (13.5%) | |
| Pleural effusion† | 12 (5.6%) | 5,947 (13.0%) | 0.001 |
*, data from the subset recorded from 2004; †, data from the subset recorded from 2010. IMA, invasive mucinous adenocarcinoma; NMA, nonmucinous adenocarcinoma.