CD274 and small cell lung carcinoma: Not all lung cancer indications require a PD-L1 protein measurement, including the first-line treatment of patients with squamous or non-squamous NSCLC as a single agent or in combination with carboplatin and either paclitaxel or nab-paclitaxel (18, 19) or patients with SCLC with disease progression on or after platinum-based chemotherapy, and at least one other prior line of therapy (20, 21).