Clinical outcome of reflex EGFR mutation and ALK fusion testing in patients with non-squamous non-small cell lung cancer

IntroductionReflex molecular testing plays a critical role in identifying actionable targets and allocating patients to appropriate treatment. We report the clinicopathologic features and treatment outcomes of non-squamous non-small cell lung cancer (NSCLC) patients who underwent reflex testing for EGFR and ALK.MethodsWe analyzed the data of NSCLC patients diagnosed from 2010 to 2014 who underwent reflex testing for EGFR (from 2010) and ALK (from 2012) alterations and compared the outcome of those positive for the alterations against those who were wild-type (WT). Using multivariate cox regression, we determined the significant prognostic clinical factors that predicted for an improved survival outcome.ResultsEGFR mutation was more prevalent among females and never-smokers. The median OS (months) for the positive group was 24.8 versus 13.3 for the WT group (p<0.001). Significant prognostic factors included ethnicity, smoking status, stage, histology, number of symptoms, ECOG status, number of metastatic sites, treatment intention and EGFR tyrosine kinase inhibitor (TKI) treatment (all p<0.02). ALK fusion was more prevalent among Malay patients (p=0.031). There were no significant survival differences in OS between positive and WT groups. Prognostic factors include gender, ethnicity, ECOG status, treatment intent, number of palliative treatment and metastatic sites (all p<0.02) and possibly ALK TKI treatment (p=0.06).ConclusionThis study found significant differences in demographic and clinical characteristics, and treatment outcomes between positive and WT patients for EGFR and ALK profiles, reinforcing the importance of reflex testing in patient management.