Epidermal Growth Factor Receptor Gene Mutation in Pleural Lavage Cytology Findings of Primary Lung Adenocarcinoma Cases

Purpose In the present study, we examined the relationship between intraoperative pleural lavage cytology findings and presence of epidermal growth factor receptor (EGFR) gene mutations. Methods We investigated 160 patients who underwent surgical treatment for primary lung adenocarcinoma at our hospital from January 2011 to December 2013 to determine the presence of EGFR gene mutations and pleural lavage cytology. Results In all, 52 subjects (31.5%) were positive EGFR gene mutations, of whom 38 were found to possess the Exon 21 L858R mutation. Intraoperative pleural lavage cytology examinations were performed in 160 subjects and 12 had positive results, of whom 6 were positive for EGFR gene mutations, which was the Exon 21 L858R mutation in all. In a comparison between subjects possessing the Exon 21 L858R mutation and those negative for EGFR gene mutations, lavage cytology-positive (p = 0.02) and vascular infiltration-negative (p = 0.01) were characteristics of the Exon 21 L868R mutation-positive group. Conclusion Subjects positive for the EGFR Exon 21 L858R mutation had a higher positive rate of intraoperative pleural lavage cytology than those not possessing EGFR mutations.