EGFR Exon 20 insertion: Prognostic and predictive values in advanced non-small cell lung cancer, a real-world study.
Authors: Chouaid Christos , Filleron Thomas , Debieuvre Didier , Perol Maurice , Girard Nicolas , Dansin Eric , Gervais Radj , Cousin Sophie , Otto Josiane , Schott Roland , Planchard David , Madroszyk Anne , Kaderbhai Coureche , Dubray-Longeras Pascale , Hiret Sandrine , Pichon Eric , Clement-Duchene Christelle Anne , Martin Anne-Laure , Simon Gaetane , Quantin Xavier 
Published: June 2021

9062 Background: In Europe, 10-15% of non-squamous non-small cell lung cancer (nsqNSCLC) have EGFR mutations of which 5-12% are an Exon 20 insertion (20ins). Methods: Analysis of Epidemio-Strategy and Medical Economics (ESME) Advanced and Metastatic Lung cancer (AMLC) Data Platform (NCT03848052), a multicenter real-life database using a supervised, retrospective data collection process. The database includes 13737 advanced nsqNSCLC treated from January 2015 at participating centres. The cut-off date for patient follow-up for this analysis was June 30, 2020. The aim of the study was to assess real-world patient characteristics, treatment patterns and clinical outcomes of advanced nsqNSCLC EGFR 20ins. Overall survival (OS) of EGFR cohorts (20ins, 19del/L858R without 20ins, other EGFR mutations) and EGFR wild-type/not tested cohort were assessed. Results: 1549 (11.3%) nsqNSCLC had an EGFR mutation, 61 (3.9%) of whom being an EGFR 20ins. These 61 patients (pts) are mainly female (68.9%), non-smoker (55.7%), with de novo stage IIIB/IV disease (78.6%), PS 0-1 (76.9%). Median age was 68.0 years (q1-q3: 54-74). PD-L1 status was assessed in 34 (55.7%) pts, mainly (n = 20) before first line and 22 (64.7%) had negative result. Most (63.9%) pts had EGFR 20ins positive result available before first line. Almost all pts (95.1%, n = 58) received a systemic therapy with a median number of 3 (q1-q3: 1-4) lines. In first line setting, 74% of the pts received chemotherapy (mainly chemotherapy combination), 13.7% received EGFR TKI (mainly as monotherapy) and 8.6% received immunotherapy only. Median treatment duration for pts treated with CarboPem (n = 19), CisplatinPem (n = 16) and CarboTaxol (n = 6) were 4.7 (q1-q3: 2.6-6.6), 7.4 (q1-q3: 5.0-12.8) and 3.3 (q1-q3: 2.8-3.8) months, respectively. For afatinib (n = 3), erlotinib (n = 2) and gefitinib (n = 1), median treatment durations were 1.6 (q1-q3: 0.5-2.8); 1.8 (q1-q3: 1.4-2.1) and 2.3 months, respectively. After a median follow up of 36.3 (95%CI: 34.1-39.8) months, median OS was 24.3 (95%CI: 19.1-32.6) months; 1 and 2-years OS rates were 82.5% (95%CI: 69.7-90.2) and 52.6% (95%CI: 37.3-65.9), respectively. For pts with 19del/L858R without 20ins (n = 1049) and those with other EGFR mutations (n = 439) median OS were 35.4 (95%CI: 32.6-37.5) and 41.7 (95%CI: 31.9-53.5), respectively compared to 20.7 (95%CI: 20.0-21.8] months for pts EGFR wild type/not tested (n = 12188). Conclusions: This large, national real-world analysis based on medical chart data’s confirm that EGFR 20ins is a rare disease (0.4% of advanced nsqNSCLC). Currently available EGFR TKIs appear to have low efficacy and response to chemotherapy seems identical to that of EGFR wild-type/not tested pts. Prognosis for NSCLC pts with EGFR 20ins mutations was in line with that of EGFR wild type/not tested but worse than common EGFR mutations highlighting the need for advancements for this rare population.