Predictive Value of EGFR Mutation Status for First-Line Tyrosine Kinase Inhibitor Treatment in Patients with Advanced Lung Cancer.

Objective:This study aims to investigate and analyze the correlation between EGFR-TKI first-line therapy and EGFR mutation status in patients with advanced lung cancer. Methods:We selected 60 patients with advanced lung cancer and EGFR mutations (diagnosed as stage IIIb or IV) from our hospital between January 2019 and November 2022. Each patient underwent an EGFR mutation test and was categorized into two groups based on their mutation status: 28 patients with exon 21 mutations and 32 with exon 19 deletions. After three months of therapy, we assessed treatment efficacy and adverse reactions. Results:Our data revealed that in the EGFR exon 21 mutation group, the objective response rate (ORR) and disease control rate (DCR) were 57.14% and 60.71%, respectively. In the EGFR exon 19 deletion group, the ORR and DCR were 68.75% and 84.38%, respectively. There were significant differences in DCR and ORR between the two EGFR mutation states, with statistical significance (P < .05). The progression-free survival (PFS) in the EGFR exon 21 mutant group was 8.4 months after third-generation EGFR-TKI treatment, while the EGFR exon 19 deletion group had a PFS of 12.7 months after the same treatment, with a statistically significant difference (P < .05). Cox regression analysis showed that female patients with no smoking history and an adenocarcinoma pathological type had significantly better PFS after treatment compared to male patients with a smoking history and squamous cell carcinoma type, with statistical significance (P < .05). Age and clinical stage did not significantly impact PFS after third-generation EGFR-TKI treatment (P > .05). Adverse reaction incidences, such as nausea, fatigue, diarrhea, vomiting, and rash, did not significantly differ in either the EGFR exon 21 mutation group or the EGFR exon 19 deletion group (P > .05). Conclusion:The status of EGFR mutations serves as a predictive factor for PFS, DCR, and ORR in lung cancer patients undergoing EGFR-TKI first-line therapy. This status can be a valuable predictive indicator of lung cancer treatment efficacy, with potential applications in clinical practice.