e21709 Background: Molecular profiling of lung adenocarcinoma is essential for therapeutic decision-making and prognosis predicting. Pleural effusion may provide an opportunity for molecular profiling and thereby possibly provide information enabling targeted therapy. In this study, we performed next generation sequencing (NGS) in pleural effusion samples in order to study molecular profiling of lung adenocarcinoma using pleural effusion specimens. Methods: 45 Chinese lung adenocarcinoma patients with pleural effusion specimens were included. The pleural effusion samples were centrifugated, then cell pellets were collected and prepared into cell blocks. Genetic mutations were assessed using a validated targeted next generation sequencing assay. Immunohistochemistry (IHC) of PD-L1 was performed with 22C3 kit. Results: In 45 pleural effusion samples collected, 43 (95.5%) patients had at least one mutation classed as pathogenic or likely pathogenic. There were 245 somatic mutation and 160 germline mutations were detected, with an average of 8.0 mutations per patient. Of the 45 specimens with somatic mutations, seventeen (37.8%) of harbored EGFR mutations. The most frequent mutations were the deletion mutation in exon19 (15/17, 40.9%), the point mutation (L858R) in exon 21 (13/17, 76.5%), and resistance mutation (T790M) in exon 20(4/17,23.5%). Aside from the EGFR mutation, 1 case exhibited KRAS mutation (G12C), 1 case harbored ERBB2 mutation(Y772_A775dup),1 case harbored TP53 mutation, and 2 cases exhibited fusion (EML4-ALK, KIF5B-RET). 2 cases exhibited CD274 copy number gain, 2 cases exhibited CDK4 copy number gains, and one case carried CDK6 copy number gain, one case carried CKD6 copy number loss. The top frequent germline mutation genes were APC (5/45), ALK (4/45), ARID1A (4/45) and BARD1 (4/45). Regarding biomarkers for immunotherapy, three sample showed TMB-H (6.7%), and one sample showed MSI-H (2.2%). Of 29 samples underwent PDL1 IHC test, 21 samples (72.4%) show positive PDL1 expression, in concordance with previous reported rates. Conclusions: These results suggest that pleural effusions are important specimens for oncogene mutation analysis and enable targeted therapy for patients with lung adenocarcinoma.
Author Correction: Comprehensive molecular profiling of lung adenocarcinoma
