Table 2. Characteristics of Nodules, Overall and Stratified by With and Without Emphysema.
| Parameter | All nodules (N = 7,090) | N group (n = 4,737) | E + N group (n = 2,353) | P value |
|---|---|---|---|---|
| Size, mm | < 0.001 | |||
| 4 - 6 | 3,707 (52.4) | 2,557 (54.1) | 1,150 (49.0) | |
| 7 - 10 | 2,120 (30.0) | 1,391 (29.4) | 729 (31.1) | |
| 11 - 20 | 937 (13.3) | 599 (12.7) | 338 (14.4) | |
| 21 - 30 | 197 (2.8) | 114 (2.4) | 83 (3.5) | |
| > 30 | 109 (1.5) | 64 (1.4) | 45 (1.9) | |
| Localization | 0.013 | |||
| Right upper | 1,733 (24.4) | 1,137 (24.0) | 596 (25.3) | |
| Right middle | 971 (13.7) | 669 (14.1) | 302 (12.8) | |
| Right lower | 1,681 (23.7) | 1,145 (24.2) | 536 (22.8) | |
| Left upper | 1,019 (14.4) | 638 (13.5) | 381 (16.2) | |
| Lingula | 304 (4.3) | 218 (4.6) | 86 (3.7) | |
| Left lower | 1,347 (19.0) | 908 (19.2) | 439 (18.7) | |
| Other | 35 (0.5) | 22 (0.5) | 13 (0.6) | |
| Margins | < 0.001 | |||
| Spiculated | 865 (12.2) | 462 (9.8) | 403 (17.1) | |
| Smooth | 4,407 (62.2) | 3,000 (63.3) | 1,407 (59.8) | |
| Poorly defined | 1,467 (20.7) | 983 (20.8) | 484 (20.6) | |
| Unable to determine | 351 (5.0) | 292 (6.2) | 59 (2.5) | |
| Component | 0.004 | |||
| Soft tissue | 5,182 (73.1) | 3,417 (72.1) | 1,765 (75.1) | |
| Ground glass | 1,093 (15.4) | 782 (16.5) | 311 (13.2) | |
| Mixed | 389 (5.5) | 259 (5.5) | 130 (5.5) | |
| Other | 423 (6.0) | 278 (5.9) | 145 (6.2) |
P values from the χ2 test. N group: nodules without emphysema; E + N group: nodules with emphysema.