Clinical modes of EGFR tyrosine kinase inhibitor failure and subsequent management in advanced non-small cell lung cancer

Abstract

There is no published overview of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) failure modes in advanced non-small-cell lung cancer (NSCLC). This study aimed to classify the diversity of EGFR-TKI failure, and to investigate the usefulness of clinical modes in subsequent management and prognosis. One-hundred and twenty consecutive clinical trial patients with EGFR-TKI failure were enrolled as the training set to establish a clinical model based on clinical factors. Another 107 routine patients were enrolled as the validating set according to a Bayes discriminant analysis. EGFR mutations and c-MET amplification were analyzed. Kaplan-Meier survival analysis was used to test the differences among three clinical modes and subsequent management. The duration of disease control, evolution of tumor burden, and clinical symptom were verified as feasible grouping variables. A correct grouping rate achieved 87.9%. The cohort was classified into three groups, as follows: 130 patients with dramatic progression, 42 with gradual progression, and 55 with local progression. Progression-free survivals (PFSs) for the dramatic progression, gradual progression, and local progression groups were 9.3, 12.9, and 9.2 months, respectively (P = 0.007). Overall survivals for the groups (OSs) were 17.1, 39.4, and 23.1 months, respectively (P < 0.001). TKI continuation was superior to switching chemotherapy in a subsequent setting for gradual progression (39.4 months vs. 17.8 months; P = 0.02). The difference of EGFR or c-MET among the three groups was not significant. Clinical modes of EGFR-TKI failure could favor strategies for subsequent treatment and predicting a survival benefit in advanced NSCLC.