Genetic Analyses for Adenocarcinoma of the Lung Using Immediate-Cytology-Positive Cancer Cells

ABSTRACT Background Genetic abnormality of lung adenocarcinoma (including EGFR, EML4-ALK, BRAF and HER2 mutation etc.) has led to a change in the treatment strategy of this disease. However, the number of cancer cells obtained from a transbronchial biopsy is usually quite low, making it difficult to genetic analyses. We aimed establishment of methodology by which we can take the greatest advantage for genetic analyses in the case of that only a cell sample, but not a tissue sample, is available. Materials and methods One hundred and fifty samples from bronchoscopic examinations utilized immediate cytology in patients with adenocarcinoma were analyzed for gene mutations by nested RT–PCR. Result EGFR, EML4-ALK and BRAF mutations were detected in 45, 3.5 and 1.0% in adenocarcinomas, respectively. Discussion Immediate cytology during bronchoscopy contributed to the selection of the best samples for genetic analysis. EML4-ALK fusion genes, BRAF mutations as well as EGFR mutations could be detected in a small number of cancer cells from transbronchial cytologic specimens by a nested RT–PCR. Our present strategy can be integrated into the clinical process without the additional invasive examination of patients and can take the greatest advantage at the appropriate selection of molecular-targeted therapies.