A Kawahara1, C Fukumitsu1, K Azuma2, T Taira1, H Abe1, Y Takase1, K Murata1, E Sadashima3, S Hattori4, Y Naito1, J Akiba1. 1. Department of Diagnostic Pathology, Kurume University Hospital, Kurume, Japan. 2. Division of Respirology, Neurology, and Rheumatology, Department of Internal Medicine, Kurume University School of Medicine, Kurume, Japan. 3. Department of Clinical Laboratory, Tenjinkai Shin-Koga Hospital, Kurume, Japan. 4. Department of Integrated Medicine, Biomedical Statistics, Osaka University Graduate School of Medicine, Osaka, Japan.
Abstract
INTRODUCTION: The aim of this study was to examine whether a combined test using both cell sediment and supernatant cytology cell-free DNA (ccfDNA) is more useful in detecting EGFR mutation than using cell sediment DNA or supernatant ccfDNA alone in pleural effusion of lung cancer patients. METHODS: A total of 74 lung adenocarcinoma patients with paired samples between primary tumour and corresponding metastatic tumour with both cell sediment and supernatant ccfDNA of pleural effusion cytology were enrolled in this study. Cell sediment and supernatant ccfDNA were analysed separately for EGFR mutations by polymerase chain reaction. RESULTS: Out of 45 patients with mutant EGFR in primary tumours, EGFR mutations were detected in 23 cell sediments of corresponding metastases (sensitivity; 51.1%) and 20 supernatant ccfDNA corresponding metastases (sensitivity; 44.4%). By contrast, the combined test detected EGFR mutations in 27 corresponding metastases (sensitivity; 60.0%), and had a higher sensitivity than the cell sediment or the supernatant ccfDNA alone (P < .05). Out of 45 patients with mutant EGFR, 24, three and 18 were cytologically diagnosed as positive, atypical or negative, respectively. The detection rate in the combined test was highest (95.8%) in the positive group, and mutant EGFR was also detected in four of 18 samples (22.2%) in the negative group. CONCLUSIONS: A combined test using both cell sediment DNA and supernatant ccfDNA samples increases the concordance rate of EGFR mutations between primary tumour and corresponding metastases. Our findings indicate that supernatant ccfDNA is useful even in cases where the cytological diagnosis is negative.
INTRODUCTION: The aim of this study was to examine whether a combined test using both cell sediment and supernatant cytology cell-free DNA (ccfDNA) is more useful in detecting EGFR mutation than using cell sediment DNA or supernatant ccfDNA alone in pleural effusion of lung cancerpatients. METHODS: A total of 74 lung adenocarcinomapatients with paired samples between primary tumour and corresponding metastatic tumour with both cell sediment and supernatant ccfDNA of pleural effusion cytology were enrolled in this study. Cell sediment and supernatant ccfDNA were analysed separately for EGFR mutations by polymerase chain reaction. RESULTS: Out of 45 patients with mutant EGFR in primary tumours, EGFR mutations were detected in 23 cell sediments of corresponding metastases (sensitivity; 51.1%) and 20 supernatant ccfDNA corresponding metastases (sensitivity; 44.4%). By contrast, the combined test detected EGFR mutations in 27 corresponding metastases (sensitivity; 60.0%), and had a higher sensitivity than the cell sediment or the supernatant ccfDNA alone (P < .05). Out of 45 patients with mutant EGFR, 24, three and 18 were cytologically diagnosed as positive, atypical or negative, respectively. The detection rate in the combined test was highest (95.8%) in the positive group, and mutant EGFR was also detected in four of 18 samples (22.2%) in the negative group. CONCLUSIONS: A combined test using both cell sediment DNA and supernatant ccfDNA samples increases the concordance rate of EGFR mutations between primary tumour and corresponding metastases. Our findings indicate that supernatant ccfDNA is useful even in cases where the cytological diagnosis is negative.
Authors: Karlijn Hummelink; Mirte Muller; Theodora C Linders; Vincent van der Noort; Petra M Nederlof; Paul Baas; Sjaak Burgers; Egbert F Smit; Gerrit A Meijer; Michel M van den Heuvel; Daan van den Broek; Kim Monkhorst Journal: ERJ Open Res Date: 2019-03-25