ABSTRACT

Introduction: Non-small cell lung cancer (NSCLC) with exon 20 insertion mutations accounts for 4-10% of all NSCLC patients with EGFR mutations. The primary treatment for NSCLC patients with recurrent metastatic EGFR exon 20 insertion mutations remains platinum-based doublet chemotherapy. However, there are very few studies in Vietnam evaluating the effectiveness of this treatment. Therefore, this study was conducted to evaluate the effectiveness of this therapy in the mentioned patient group.

Subjects and Methods: This is a retrospective cross-sectional descriptive study on 36 NSCLC patients with recurrent metastatic EGFR exon 20 insertion mutations treated with platinum-based doublet chemotherapy from January 2019 to June 2024 at K Hospital to evaluate treatment outcomes and adverse effects of the regimen in this patient group.

Results: The response rate of the regimen was 25%, and the disease control rate was 66.7%. The median progression-free survival (PFS) was 7.0 months. The median overall survival (OS) was 17.6 months. The majority of patients experienced at least one adverse effect, accounting for 80.6%. The most common adverse effects were neutropenia (in 58% of patients), peripheral neuropathy (44%), anemia (48%), and nausea (42%). The most common grade 3 or higher adverse effects were neutropenia (25%), thrombocytopenia (6%), and anemia (8%). Dose reductions and drug discontinuations due to adverse effects were reported in 17% and 8% of patients, respectively.

Conclusion: Platinum-based doublet chemotherapy as the first-line treatment for NSCLC patients with recurrent metastatic disease is an effective treatment with manageable toxicity.

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