| Groups | The 4th-order | The 5th-order | The 6th-order | The 7th-order | ||||
|---|---|---|---|---|---|---|---|---|
| Cases | % | Cases | % | Cases | % | Cases | % | |
| Adenocarcinoma | 2 | 6.9 | 10 | 34.5 | 23 | 79.3 | 5 | 17.2 |
| Squamous-cell carcinoma | 4 | 30.8 | 3 | 23.1 | 5 | 38.5 | 2 | 15.4 |
The data were recorded separately when a case was related to different orders of the bronchi