CD274 and non-small cell lung carcinoma: After the authorisation of admission to reimbursement of two anti-PD-1 drugs for the treatment of stage IV NSCLC, in October 2017 the Italian Association of Medical Oncology (AIOM) and the Italian Society of Pathology (SIAPEC) drafted recommendations for the immunohistochemical evaluation of PD-L1 expression as a predictive test.