Abstract 2639: Prognostic significance of non-small cell lung cancer and response to EGFR-TKI of EGFR mutated lung cancer besed on PD-L1 expression

Abstract

Listen

Translate article

Abstract Background: Recent clinical trials have shown that immune checkpoint blockades that target either PD-1 or PD-L1 yield remarkable responses in a subgroup of non-small cell lung cancer (NSCLC) patients. Materials and Methods: We retrospectively examined, by immunohistochemical analysis, 211 NSCLC patients who had undergone complete surgical resection. Using 32 independent samples, we also evaluated PD-L1 expression in 32 NSCLC patients with epidermal growth factor receptor (EGFR) mutations treated by EGFR-tyrosine kinase inhibitors (EGFR-TKIs). Results: Overall survival of PD-L1 positive surgical NSCLC patients with stages I-III and stage I disease were significantly shorter than those of PD-L1 negative NSCLC patients (P <0.01 and P = 0.02, respectively). In 86 squamous cell carcinoma (SQ) cases, PD-L1 positive patients showed significantly poorer survival than PD-L1 negative patients (P = 0.01). In stage I NSCLC patients, gender and PD-L1 expression were found to be independent predictors of death after multivariate analysis (Hazard ratio [HR] 3.57, P <0.01 and HR 2.05, P = 0.04, respectively). In SQ patients, p-stage and PD-L1 expression were independent predictors of death (HR 2.53, P <0.01 and HR 2.26, P = 0.02, respectively). Response to EGFR-TKIs, progression-free survival and overall survival were not significantly different between PD-L1 positive and negative NSCLC patients with EGFR mutations. Conclusion: PD-L1 positive expression in a tumor was a significant independent predictor of poor outcome in patients with lung SQ and in stage I NSCLC patients. Based on PD-L1 expression, the clinical response to EGFR-TKIs and prognosis did not differ in EGFR-mutated NSCLC patients. Citation Format: Kenichi Kobayashi, Masahiro Seike, Rintaro Noro, Shinobu Hemmi, Akihiko Gemma. Prognostic significance of non-small cell lung cancer and response to EGFR-TKI of EGFR mutated lung cancer besed on PD-L1 expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2639.