OBJECTIVES : Non-Small Cell Lung Cancer (NSCLC) is the leading cause of cancer death worldwide. Clinical trials have established the role of Programmed Cell Death/Programmed Death Ligand 1 (PD-1/PD-L1) inhibitors for metastatic NSCLC treatment and evaluation of PD-L1 expression for treatment selection. In our ongoing observational study, we analyzed the PD-L1 testing patterns and subsequent treatment selection in metastatic NSCLC patients in Maccabi Healthcare Services (MHS).

METHODS : Newly diagnosed stage IV NSCLC patients who initiated systemic anti-cancer treatment from January to December 2017 were identified from the Israel national cancer registry. Their demographic, clinical and treatment data were collected from the MHS patient database and extracted from medical documents.

RESULTS : A total of 194 patients were diagnosed with NSCLC Stage IV and initiated first line (1L) treatment in 2017. The study population comprised of 58% males, 54% ≥65 years old, 65% current or former smokers, 81% adenocarcinomas, 12% brain metastases and 56%/11%/6%/28% with 0-1/2/3-4/Unknown ECOG performance status. A total of 76.8% (149/194) patients were tested for PD-L1, all using the 22C3 antibody on Ventana platform, of which 95% testing was carried out before the start of 1L treatment. PD-L1 tumor proportion score (TPS) ≥50% was found in 48.3% of patients tested, of which 83% received 1L PD-1 inhibitor monotherapy. Of those not tested for PD-L1 before the start of 1L treatment (n=79), 61% received treatment with a platinum doublet, 35% received tyrosine kinase inhibitor therapy and 4% received PD-1/PD-L1 inhibitor monotherapy.

CONCLUSIONS : A fast uptake of PD-L1 testing was seen since its introduction in the Israel’s health services list in early 2017. A relatively high PD-L1 positive rate was seen which needs further validation as study size increases. Predominant use of immune checkpoint inhibitors as 1L treatment for PD-L1 positive patients shows high adherence to guidelines.