Table 2. Lung cancers according to the smoking status.
| Characteristics | Never-smoker | Pack-years <30 | Pack-years ≥30 | Total |
|---|---|---|---|---|
| No. of patients [no. of lesions§] | ||||
| Men | 16 [18] | 21 [22] | 34 [39] | 71 [79] |
| Women | 50 [59] | 10 [12] | 2 [2] | 62 [73] |
| Maximal diameter of the lesions (cm)* | 1.5±0.8 | 1.3±0.8 | 1.4±0.8 | 1.4±0.8 |
| No. of lesions | 77 (100.0) | 34 (100.0) | 41 (100.0) | 152 (100.0) |
| Consistency of the lesions [n=152], n (%) | ||||
| Pure GGN | 14 (18.2) | 7 (20.6) | 11 (26.8) | 32 (21.1) |
| Part-solid | 49 (63.6) | 19 (55.9) | 11 (26.8) | 79 (52.0) |
| Solid | 12 (15.6) | 8 (23.5) | 16 (39.0) | 36 (23.7) |
| Others¶ | 2 (2.6) | 0 (0.0) | 3 (7.3) | 5 (3.3) |
| Histology [n=152], n (%) | ||||
| Adenocarcinoma | 75 (97.4) | 30 (88.2) | 30† (73.2) | 135† (88.8) |
| Squamous cell carcinoma | 0 (0.0) | 0 (0.0) | 8 (19.5) | 8 (5.3) |
| Small cell carcinoma | 0 (0.0) | 1 (2.9) | 2†† (4.9) | 3†† (2.0) |
| Adenosquamous carcinoma | 0 (0.0) | 1 (2.9) | 0 (0.0) | 1 (0.7) |
| Carcinoid | 2 (2.6) | 0 (0.0) | 0 (0.0) | 2 (1.3) |
| NSCLC | 0 (0.0) | 1 (2.9) | 0 (0.0) | 1 (0.7) |
| Atypical cell** | 0 (0.0) | 1 (2.9) | 1 (2.4) | 2 (1.3) |
| Stage¶¶ [n=152], n (%) | ||||
| IA | 70 (90.9) | 29 (85.3) | 31 (75.6) | 130 (85.5) |
| IB | 4 (5.2) | 4 (11.8) | 4 (9.8) | 12 (7.9) |
| IIA | 0 (0.0) | 0 (0.0) | 1 (2.4) | 1 (0.7) |
| IIB | 0 (0.0) | 1 (2.9) | 0 (0.0) | 1 (0.7) |
| IIIA | 0 (0.0) | 0 (0.0) | 3 (7.3) | 3 (2.0) |
| IIIB | 2 (2.6) | 0 (0.0) | 1 (2.4) | 3 (2.0) |
| IV | 1 (1.3) | 0 (0.0) | 1 (2.4) | 2 (1.3) |
| First-line treatment [n=152], n (%) | ||||
| Surgery only | 76 (98.7) | 30 (88.2) | 34 (82.9) | 140 (92.1) |
| Surgery and radiotherapy | 1 (1.3) | 0 (0.0) | 0 (0.0) | 1 (0.7) |
| Surgery and chemotherapy | 0 (0.0) | 1 (2.9) | 1 (2.4) | 2 (1.3) |
| Chemotherapy and radiotherapy | 0 (0.0) | 0 (0.0) | 3 (7.3) | 3 (2.0) |
| Radiotherapy | 0 (0.0) | 2 (5.9) | 1 (2.4) | 3 (2.0) |
| Ablation‡ | 0 (0.0) | 1 (2.9) | 0 (0.0) | 1 (0.7) |
| N/A | 0 (0.0) | 0 (0.0) | 2 (4.9) | 2 (1.3) |
§, lesions: nodules, masses, and other than nodules or masses; *, mean ± SD; ¶, five lesions other than nodules or masses were diagnosed as lung cancers: a funicular-like opacity (n=1), a heterogeneous opacity in pulmonary fibrosis (n=1), hilar enlargement (n=1), a pneumonia-like opacity (n=1), and a cyst with a thick wall (n=1); †, one adenocarcinoma was diagnosed cytologically using fiberoptic bronchoscopic examination; ††, one cancer was an interval case; **, cytologic diagnosis using fiberoptic bronchoscopic examination; ¶¶, 7th TNM classification (the results based on the 8th edition of TNM staging system are shown in Table S1); ‡, this patient had double primary adenocarcinomas; one was resected and the other was treated by ablation in accordance with the patient’s wish; N/A, data were not available due to transfer of the patients to other hospitals. GGN, ground-glass nodule; NSCLC, non-small cell lung cancer.