PDCD1 and non-small cell lung carcinoma: Based on the impressive response rates in several other malignancies, e.g. non-small cell lung carcinoma and melanoma, blocking of the programmed cell death protein 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) signaling pathway currently represents one the most intensively investigated immune therapies for the treatment of PDAC [7].