Summary of specimen preparation
| n (%) | Patients with advanced OC, n=482 |
| Biopsy source | |
| Newly obtained* | 19 (3.9) |
| Archival | 463 (96.1) |
| Biopsy site | |
| Primary tumour | 476 (98.8) |
| Lymph node | 3 (0.6) |
| Metastatic lesion† | 3 (0.6) |
| Biospecimen type | |
| Biopsy | 138 (28.6) |
| Surgical resection | 344 (71.4) |
*Defined as tissue collected within 6 weeks of the PD-L1 test.
†Metastatic lesion samples were decalcified bone specimens.
OC, oesophageal cancer; PD-L1, programmed death ligand 1.