Prognostic Value of EGFR Exon-20 Insertions in Czech Patients With Advanced Non-small Cell Lung Cancer.

BACKGROUND/AIM: Per literature, patients with epidermal growth factor receptor (EGFR) exon-20 insertions respond poorly to tyrosine kinase inhibitors (TKIs). This study analyzed real-world data to examine the prognostic and predictive value of these mutations. PATIENTS AND METHODS: We conducted a retrospective cohort study using Czech TULUNG Registry data, with data on multiple mutation types, collected in 2011-2020. RESULTS: We analyzed 554 (95.85%) patients with EGFR exon-19 deletions or exon-21 L858R substitutions and 24 (4.15%) patients with exon-20 insertions who received first-line high-value therapies. We summarized clinical characteristics and outcomes in all patients and by cohort. The risk of progression was statistically significantly higher (86%) in the exon-20 insertion cohort compared to the cohort with other mutations. Although not statistically significant, the risk of death was 44% higher in patients with exon-20 insertions. CONCLUSION: Advanced NSCLC patients with rare EGFR exon-20 insertions have a high risk of progression.

Comparison of Chemotherapeutic Regimens Frequently Used in Metastatic Non-squamous NSCLC Treatment.

BACKGROUND/AIM: Platinum-based chemotherapy with pemetrexed or paclitaxel/bevacizumab are regimens used in combination with checkpoint inhibitors in non-squamous non-small cell lung cancer (NSCLC) treatment. We conducted a real-world study to compare the outcomes of these chemotherapeutic regimens. PATIENTS AND METHODS: We investigated 1,534 patients with advanced non-squamous NSCLC treated with platin/pemetrexed (n=1212) or platin/paclitaxel/bevacizumab (n=322) in 9 cancer centres in the Czech Republic. RESULTS: The regimen containing platin/paclitaxel/bevacizumab showed significantly better overall response rate (ORR) compared to the platin/pemetrexed [40.8% vs. 32.7% (p=0.008)] in the overall population and [55.0% vs. 38.8% (p=0.002)] in the Eastern Cooperative Oncology Group performance status 0 group. There was no significant improvement in progression-free survival (PFS) and overall survival (OS) in either of these two groups of patients. CONCLUSION: In our real-world data analysis, patients treated with platin/paclitaxel/bevacizumab had better overall response rate (ORR), but not PFS or OS. Thus, both treatment regimens are similarly effective. Their selection should therefore be based on the potential side effects.

Real-life Effectiveness of Afatinib Versus Gefitinib in Patients With Non-small-cell Lung Cancer: A Czech Multicentre Study.

BACKGROUND/AIM: We investigated efficacy differences for afatinib versus gefitinib in non-small-cell lung cancer (NSCLC) according to epidermal growth factor receptor (EGFR) mutations. PATIENTS AND METHODS: We retrospectively analysed data for 343 patients with NSCLC with performance status 1 having EGFR mutations treated with gefitinib or afatinib. Overall response rate (ORR) was tested by Fisher's exact test. Overall (OS) and progression-free (PFS) survival were estimated by Kaplan-Meier method. RESULTS: ORR did not differ in any group or subgroup. Among all patients, we observed significantly longer PFS for those treated with afatinib vs. gefitinib (median 13.4 vs. 9.5 months, p=0.026), but only a nonsignificant trend was observed for OS. We showed nonsignificant trends of better PFS and OS using afatinib for exon 19 deletion and L858R subgroups. We observed no significant PFS differences for other EGFR mutations but a nonsignificant trend towards better OS for those treated with afatinib. CONCLUSION: Afatinib led to longer PFS for patients with common EGFR mutations but not for those with rare mutations.

Real-life effectiveness of first-line anticancer treatments in stage IIIB/IV NSCLC patients: Data from the Czech TULUNG Registry.

BACKGROUND: Data regarding real-life effectiveness of any treatment may improve clinical decision-making. The aim of this study was to evaluate real-life effectiveness of tyrosin-kinase inhibitors, bevacizumab and pemetrexed as first-line treatments in patients with advanced/metastatic non-small cell lung cancer (NSCLC). METHODS: We analyzed data of 2157 patients of the Czech TULUNG Registry of patients with advanced/metastatic NSCLC who received modern-era treatments between 2011 and 2018. Patients treated with gefitinib, erlotinib, afatinib, bevacizumab (+ maintenance), pemetrexed (+ maintenance) as first-line therapy were included in the study. A systematic literature search separately identified clinical trials suitable for calculation of comparator pooled OS and PFS for each regimen. For each subgroup, basic characteristics and survival data (Kaplan-Meier estimates) are shown. We propose the "index of real-life effectiveness" (IRE), a ratio of real-life OS/PFS and comparator pooled OS/PFS. Univariate and multivariate logistic regression identified factors were associated with longer OS (ie, IRE>1.1). RESULTS: Survival analysis showed median OS of 23 months for erlotinib, 29.3 months for afatinib, 19.6 months for gefitinib, 12.2 months for pemetrexed, 17.5 months for pemetrexed maintenance, 15.8 months for bevacizumab and 15.8 months for bevacizumab maintenance. Calculated IREs for OS for the regimens were: erlotinib 1.013, afatinib 1.184, gefitinib 0.736, pemetrexed 1.188, pemetrexed maintenance 1.294, bevacizumab 1.178, and bevacizumab maintenance 1.189. Multivariate regression analysis showed that these factors were associated with longer OS: lower PS for afatinib; lower PS, absence of adverse events and female sex for bevacizumab; and lower PS and female sex for pemetrexed. CONCLUSIONS: This study clearly demonstrated that real-life effectiveness of certain treatment regimens may strongly differ in various populations/health care systems, and comparison between TULUNG data and pooled survival data from trials showed higher real-life effectiveness for most of the studied first-line regimens. Lower ECOG PS, younger age, female sex and adverse events were associated with longer survival in most regimens. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: Comparison between TULUNG data and pooled survival data from trials showed higher real-life effectiveness for most of the studied first-line regimens; for most regimens, lower ECOG PS, younger age, female sex and adverse events were associated with longer survival. WHAT THIS STUDY ADDS: Real-life effectiveness of certain treatment regimens may strongly differ in various populations/health care systems.

Afatinib in the Treatment of Advanced Non-Small Cell Lung Cancer with Rare EGFR (in exon 18-T179X) Mutation - a Case Report.

INTRODUCTION: Exon 18-T719X EGFR mutation in non-small cell lung cancer is rare, only 1-5% of all EGFR mutations. The efficacy of EGFR tyrosin kinase inhibitors in tumours with uncommon mutations is still unclear and the prediction of response of such tumours to therapy remains unexplored. CASE: A 71-year-old woman with no previous smoking history with disseminated lung adenocarcinoma with exon 18-T719X EGFR mutation was treated with afatinib. A partial response was achieved in 2 months, progression-free survival was 19 months. The dose of afatinib was reduced to 30mg/day after 3 months due to skin toxicity and stomatitis grade 2. Next reduction to 20mg/day was performed after 10 subsequent months due to leucopenia and neutropenia grade 2. CONCLUSION: With this patient, a partial response which lasted 19 months despite 50% reduction of the afatinib dose was achieved. Key words: afatinib - non-small cell lung cancer - epidermal growth factor-mutation receptor - treatment outcome - drug toxicity This article was supported by Boehringer Ingelheim. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 27. 9. 2018 Accepted: 1. 10. 2018.