Patients were required to be PD-L1 positive by immunohistochemistry (IHC), which was defined as PD-L1 positivity in the stroma or ≥1% tumour cells using their Qualtek assay.28 Most patients were heavily pre-treated; the median number of previous lines of systemic therapy for metastatic disease was two, with 46.9% of patients having received at least three lines of prior therapy and 25.0% having received at least five. This evidence concerns the gene CD274 and neoplasm.