Table 4. Comparison of clinicopathological characteristics between the LAP group and the MS group in patients with stage I lung adenocarcinoma* after curative resection.
| Variables | LAP group (n=556) | MS group (n=53) | P value |
|---|---|---|---|
| Age (±SD) | 63.9 (±10.2) | 66.13 (±9.5) | 0.129 |
| Sex | 0.001 | ||
| Male | 212 (38.1) | 33 (62.3) | |
| Female | 344 (61.9) | 20 (37.7) | |
| Former or current smokers | 154 (27.7) | 26 (49.1) | 0.002 |
| FEV1 (%) (±SD) | 96.5 (±17.0) | 91.9 (±18.2) | 0.066 |
| DLCO (%) (±SD) | 89.6 (±16.6) | 81.2 (±16.8) | 0.001 |
| Involved lobes | 0.146 | ||
| Right upper | 182 (32.7) | 24 (45.3) | |
| Right middle | 51 (9.2) | 6 (11.3) | |
| Right lower | 116 (20.9) | 6 (11.3) | |
| Left upper | 122 (21.9) | 13 (24.5) | |
| Left lower | 85 (15.3) | 4 (7.5) | |
| Operation | 0.107 | ||
| Wedge resection | 50 (9.0) | 8 (15.1) | |
| Segmentectomy | 57 (10.3) | 1 (1.9) | |
| Lobectomy | 443 (79.7) | 44 (83.0) | |
| Bilobectomy | 6 (1.1) | 0 | |
| Surgical approach | 0.148 | ||
| VATS | 506 (91.0) | 45 (84.9) | |
| Open thoracotomy | 50 (9.0) | 8 (15.1) | |
| Extent of Lymph node dissection | 0.002 | ||
| No mediastinal lymph node dissection | 59 (10.6) | 5 (9.4) | |
| Mediastinal lymph node sampling | 64 (11.5) | 15 (28.3) | |
| Mediastinal lymph node dissection | 433 (77.9) | 33 (62.3) | |
| Postoperative hospital stay (days) | 6.7 (±8.2) | 7.7 (±11.5) | 0.410 |
| Postoperative complications | 71 (12.8) | 7 (13.2) | 0.927 |
| Surgical mortality | 1 (0.2) | 0 | 1.000 |
| Stage (TNM-8) | <0.001 | ||
| IA1 | 175 (31.5) | 3 (5.7) | |
| IA2 | 195 (35.1) | 12 (22.6) | |
| IA3 | 56 (10.1) | 13 (24.5) | |
| IB | 130 (23.4) | 25 (47.2) | |
| Histologic subtypes (predominant pattern) | |||
| Lepidic adenocarcinoma | 144 (25.9) | 0 | |
| Acinar adenocarcinoma | 345 (62.1) | 0 | |
| Papillary adenocarcinoma | 67 (12.1) | 0 | |
| Micropapillary adenocarcinoma | 0 | 15 (28.3) | |
| Solid adenocarcinoma | 0 | 38 (71.7) | |
| Total tumor size (including lepidic component) | 2.2 (±0.9) | 2.4 (±0.9) | 0.073 |
| Invasive component size | 1.5 (±0.8) | 2.3 (±0.8) | <0.001 |
| Number of dissected lymph nodes | 11.9 (±7.5) | 12.3 (±10.0) | 0.796 |
| Visceral pleural invasion | 112 (20.1) | 19 (35.8) | 0.008 |
| Lymphovascular invasion | 191 (34.4) | 30 (56.6) | 0.001 |
*, excluding adenocarcinoma in situ and minimally invasive adenocarcinoma. LAP group: lepidic adenocarcinoma, acinar adenocarcinoma, papillary adenocarcinoma; MS group: micropapillary adenocarcinoma, solid adenocarcinoma. SD, standard deviation; FEV1, forced expiratory volume in 1 second; DLCO, diffusing capacity for carbon monoxide; VATS, video-assisted thoracoscopic surgery; TNM-7, 7th edition of the tumor node metastasis staging system; TNM-8, 8th edition of the tumor node metastasis staging system.