First-line Afatinib in Epidermal Growth Factor Receptor–mutant Metastatic Non-small Cell Lung Cancer: a Clinical Retrospective Study

Background: We sought to analyse epidermal growth factor receptor mutated (EGFR-MT) metastatic non-small cell lung cancer (NSCLC) patients treated with afatinib as first-line therapy in a clinical setting. The outcomes of cases, especially those harbouring rare mutations, were reviewed.Methods: A single-centre retrospective study of 85 patients with NSCLC treated with first-line afatinib was performed. Demographics, clinical data, and treatment information were used to assess the effects of age, mutation types (common/ uncommon), Eastern Cooperative Oncology Group performance status (ECOG PS), presence of brain metastasis, and other factors on progression-free survival (PFS) and overall survival (OS).Results: Median age was 63 years. ECOG PS >= 2 was present in 10.6% of cases. A total of 11.8% of all cases had brain metastasis at first presentation and 41.2% had uncommon mutations. The median PFS was 14.9 months; the median OS was 33.9 months. 91.8% of patients experienced treatment-related adverse effects. Dose reductions were required for 30.6% of cases. Patients with major uncommon mutations had PFS of similar lengths to those with common mutations. Age, presence of brain metastasis, ECOG PS of >= 2 and presence of exon 20 insertions correlated negatively with PFS and OS.Conclusions: Afatinib is an effective first-line treatment for patients with EGFR-MT NSCLC. The drug is well tolerated, with good response rates across a broad spectrum of patients. Given its high efficacy in major uncommon mutations, it should be considered as first-line treatment in this subset.