PT  - JOURNAL ARTICLE
AU  - MARIA BASSANELLI
AU  - STEFANO SIOLETIC
AU  - MAURIZIO MARTINI
AU  - SILVANA GIACINTI
AU  - ANTONELLA VITERBO
AU  - ANITA STADDON
AU  - FABRIZIO LIBERATI
AU  - ANNA CERIBELLI
TI  - Heterogeneity of PD-L1 Expression and Relationship with Biology of NSCLC
AID  - 10.21873/anticanres.12662
DP  - 2018 Jul 01
TA  - Anticancer Research
PG  - 3789--3796
VI  - 38
IP  - 7
4099  - http://ar.iiarjournals.org/content/38/7/3789.short
4100  - http://ar.iiarjournals.org/content/38/7/3789.full
SO  - Anticancer Res2018 Jul 01; 38
AB  - Immunotherapy with monoclonal antibodies against programmed cell death (PD-1), such as nivolumab and pembrolizumab, has significantly improved the survival of patients with metastatic non-small cell lung cancer (NSCLC). In order to determine the subset of patients that can benefit most from these therapies, biomarkers such as programmed death ligand-1 (PD-L1) have been proposed. However, the predictive and prognostic role of the use of PD-L1 is controversial. Anti-PD-L1 immunohistochemistry may not represent the actual status of the tumour because of individual variability and tumour heterogeneity. Additionally, there may be analytical variability due to the use of different assays and antibodies to detect PD-L1. Moreover PD-L1 expression is also regulated by oncogenic drivers in NSCLC, such as epidermal growth factor receptor (EGFR), echinoderm microtubule-associated protein-like 4 (EML4) fusion with anaplastic lymphoma kinase (ALK), and Kirsten rat sarcoma viral oncogene homolog (KRAS). Preclinical studies have shown the potential role of targeted therapy in immune escape mechanisms in NSCLC cells. This review summarizes current literature data on the heterogeneity of PD-L1 expression and the relationship with such factors and with clinicopathological features of NSCLC.