Clinical Research of EGFR and KRAS Mutation in Fine Needle Aspiration Cytology Specimens of Non-small Cell Lung Carcinoma

Background and objective Epidermal growth factor receptor (EGFR) and KRAS must be detected mutation status before patients of lung cancer use targeted drugs. The aim of this study is to elucidate the significance of EGFR and KRAS mutation in fine needle aspiration (FNA) cytology suspension specimens of non-small cell lung carcinoma. Methods EGFR gene exons 18-21 and KRAS codons 12, 13 of exons 2 were performed by Real-time PCR methods in fine needle aspiration cytology suspension specimens of lymph nodes. Results 85 metastasis lymph nodes were detected in fine needle aspiration cytology samples of lung cancer. EGFR mutation rate was 37.3%. KRAS mutation rate was 7.2%. 19 formalin fixed paraffin-embedded tissue specimens were available and match cytology specimens. Analysis of EGFR mutation status in those samples revealed agreement with the results obtained in cytological samples (kappa=1.0). Clinical follow-up was available for 13 who presented with stage IV disease. Based on the identification of such mutations, these patients received subsequent therapy with a TKI in clinic. We observed two cases complete remission (16.7%) and 8 cases partial remission (66.7%) and three had ongoing stable disease. Conclusion Fine-needle aspiration cytology samples were detected EGFR and KRAS mutation. The method which collects samples was easier, simple and convenient. This method has higher application value in clinical treatment. DOI: 10.3779/j.issn.1009-3419.2015.04.05