Table 1. Baseline characteristics of patients with stage I lung adenocarcinoma.
| Characteristic | Total (N=)2537 | non-VPI (n=1989) | VPI (n=548) | p* |
|---|---|---|---|---|
| No. | No. % | No. % | ||
| Sex | .005 | |||
| Male | 1034(40.8) | 782(39.3) | 252(46.0) | |
| Female | 1503(59.2) | 1207(60.7) | 296(54.0) | |
| Age, years | .132 | |||
| ≤65 | 1872(73.8) | 1499(75.4) | 373(68.1) | |
| >65 | 665(26.2) | 490(24.6) | 175(31.9) | |
| Tumor size(cm) | .000 | |||
| ≤2 | 1559(61.5) | 1335(67.1) | 224(40.9) | |
| 2-3 | 978(38.5) | 654(32.9) | 324(59.1) | |
| Lymphovascular invasion | .000 | |||
| Yes | 146(5.8) | 85(4.3) | 61(11.1) | |
| No | 2391(94.2) | 1904(95.7) | 487(88.9) | |
| ACT | .000 | |||
| Yes | 500(19.7) | 209(10.5) | 291(53.1) | |
| No | 2037(80.3) | 1780(89.5) | 257(46.9) | |
| Adenocarcinoma subtype | .000 | |||
| Lepidic | 226(8.9) | 221(11.1) | 5(0.9) | |
| Acinar | 1209(47.7) | 922(46.4) | 287(52.4) | |
| Papillary | 1002(39.7) | 786(39.5) | 216(39.4) | |
| Micropapillary | 13(0.5) | 8(0.4) | 5(0.9) | |
| Solid | 87(3.4) | 52(2.6) | 35(6.4) | |
| TNM | .000 | |||
| Ia1 | 291(11.5) | 291 | 0 | |
| Ia2 | 1044(41.1) | 1044 | 0 | |
| Ia3 | 654(25.4) | 654 | 0 | |
| Ib | 548(21.6) | 0 | 548 |
Abbreviations: ACT= adjuvant chemotherapy; VPI=visceral pleural invasion
*χ2 test was calculated from logistic regression model stratified by trail. P value is for the comparison between VPI and non-VPI.