KẾT QUẢ ĐIỀU TRỊ BƯỚC MỘT BẰNG AFATINIB TRÊN UNG THƯ PHỔI KHÔNG TẾ BÀO NHỎ GIAI ĐOẠN TIẾN XA, CÓ ĐỘT BIẾN KÉP EGFR TẠI BỆNH VIỆN K

Abstract

Background: Compound EGFR mutations in non-small cell lung cancer (NSCLC) are relatively uncommon, accounting for 4–26% of EGFR-positive cases, and exhibit distinct biological characteristics and treatment responses compared to single mutations. Afatinib, a second-generation EGFR-TKI, has demonstrated efficacy in this subgroup; however, data in Vietnam remain limited. Subject and method: We retrospectively analyzed 58 patients with advanced-stage (IIIC–IV) NSCLC adenocarcinoma harboring compound EGFR mutations, treated with first-line Afatinib at K Hospital between January 2018 and December 2024, with follow-up until July 2025. Results: The median age was 61 ± 10.4 years; male-to-female ratio was 2:1; most patients had ECOG PS 0–1. The uncommon + uncommon mutation subtype accounted for 56.9%, and common + uncommon for 41.4%. The overall response rate (ORR) was 65.5%, and disease control rate (DCR) was 91.4%. Median progression-free survival (mPFS) was 16.4 ± 2.5 months. Patients with Del19 or L858R plus another mutation achieved significantly longer mPFS compared to those without Del19/L858R (24.1 ± 5.7 vs. 11.4 ± 2.3 months; p = 0.047). Common adverse events included diarrhea (65.5%), skin toxicity (58.6%), and paronychia (43.1%); grade 3 toxicity occurred in 13.8%, with no grade 4 events. Conclusions: Afatinib is an effective first-line treatment option for advanced NSCLC patients with compound EGFR mutations, providing high response rates, favorable disease control, prolonged PFS, and manageable toxicity.