CD274 and lung carcinoma: A recent flow cytometric analysis in advanced lung cancer also supports the concept of systemic immune checkpoint expression as an association of increased numbers of PD‐L1 and PD‐L2‐positive T cells in peripheral blood with inferior survival was shown.15 This underlines the importance of considering PD‐L2 expression additional to PD‐L1 to better understand the tumorbiologic significance of PD1‐signaling.