Anaplastic lymphoma kinase (ALK)-positive and -negative tumour specimens
| ALK-positive tumours | ALK-negative tumours | p-value | |
| Specimens | 140 | 400 | |
| Type of specimen | <0.0001 | ||
| Surgical biopsies | 73 (52) | 71 (18) | |
| Surgical resections | 57 (41) | 291 (73) | |
| Data not available | 10 (7) | 36 (9) | |
| Cell blocks | 0 | 2 (<1) | |
| Sites | |||
| Lung | 72 (51.5) | 284 (71) | <0.0001 |
| Lymph node | 38 (27) | 41 (10) | <0.0001 |
| Pleura | 18 (13) | 36 (9) | 0.19 |
| Brain | 3 (2) | 22 (6) | 0.10 |
| Bone | 0 | 2 (0.5) | ns |
| Liver | 1 (1) | 0 | ns |
| Pericardium | 0 | 2 (0.5) | ns |
| Skin and soft tissues | 2 (1.5) | 2 (0.5) | ns |
| Adrenal gland | 0 | 2 (0.5) | ns |
| Not available | 6 (4) | 9 (2) | ns |
| Malignant cells % | 60 (10–100) | 60 (5–100) | 0.89 |
Data are presented as n, n (%) or mean (range), unless otherwise stated. ns: nonsignificant.