Real-World Prevalence of PD-L1 Expression Among Tumor Samples From Patients With Non-Small-Cell Lung Cancer.

INTRODUCTION: We analyzed the prevalence of non-small-cell lung cancer (NSCLC) with a programmed cell death ligand 1 (PD-L1) tumor proportion score (TPS) of ≥ 50% and compared the results with the existing data from clinical trials and databases from other countries. MATERIALS AND METHODS: The Latin American Cooperative Oncology Group and Grupo Brasileiro de Oncologia Torácica performed a retrospective, cross-sectional study from August 2017 to April 2018. PD-L1 expression was collected from pathology reports from 5 laboratories in Brazil. All tests were sponsored by the pharmaceutical industry on request from the treating medical oncologist. PD-L1 expression was assessed by immunohistochemistry. The variables were summarized as absolute and relative frequencies or the median and interquartile range. Pearson's χ2 test was used to compare the TPS categories stratified by sex, age, and histologic type. All analyses were performed with SAS, version 9.4, and were deemed statistically significant at P < .05. RESULTS: A total of 1512 patients were included in the present study. Their median age was 66 years. Most patients were men (56.02%), and the most common histologic type was adenocarcinoma (58.04%); 109 tumors (11.31%) had EGFR mutations and 34 (3.64%) had ALK gene rearrangements. Overall, 56.54% had a PD-L1 TPS < 1%, 25.63% a TPS of 1% to 49%, and 17.83% a TPS of ≥ 50%. The factors associated with PD-L1 expression were histologic type (with adenocarcinoma samples having a greater proportion of TPS < 1%) and the laboratory that performed the test. CONCLUSION: The prevalence of high PD-L1 expression among the Brazilian NSCLC samples was lower than previously described in other countries, which could affect the number of patients who might be candidates for immunotherapy alone.

Optimizing the sequencing of tyrosine kinase inhibitors (TKIs) in epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer (NSCLC).

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for 80-85% of cases. Epidermal growth factor receptor (EGFR) mutations are observed in approximately 40% and 20% of patients with NSCLC in Asian and non-Asian populations, respectively. First-generation (gefitinib, erlotinib) and second-generation (afatinib, dacomitinib) EGFR-tyrosine kinase inhibitors (TKIs) have been standard-of-care (SoC) first-line treatment for patients with sensitizing EGFR mutation positive advanced NSCLC following Phase III trials versus platinum-based doublet chemotherapy. However, most patients treated with first-line first- or second-generation EGFR-TKIs develop resistance. Osimertinib, a third-generation, central nervous system active EGFR-TKI which potently and selectively inhibits both EGFR-TKI sensitizing (EGFRm) and the most common EGFR T790 M resistance mutations, has shown superior efficacy versus first-generation EGFR-TKIs (gefitinib / erlotinib). Osimertinib is now a treatment option for patients with advanced NSCLC harboring EGFRm in the first-line setting, and treatment of choice for patients with T790 M positive NSCLC following disease progression on first-line EGFR-TKIs. The second-generation EGFR-TKI dacomitinib has also recently been approved for the first-line treatment of EGFRm positive metastatic NSCLC. There remains a need to determine appropriate sequencing of EGFR-TKIs in this setting, including EGFR-TKIs as monotherapy or in combination with other TKIs / signaling pathway inhibitors. This review considers the evolving role of sequencing treatments to maximize benefits for patients with EGFRm positive advanced NSCLC.