LAUSR

329Background: Clinical implementation of genome sequencing is recently prevailing in the treatment for cancer. We have launched an in-house clinical sequencing system to perform exhaustive targeted exome sequencing for patients with all types of cancer, as an outpatient service. We have analyzed the clinical utility of this system for patients with gastrointestinal cancer to elucidate real world evidence. Methods: Genomic DNA was extracted from tumor tissues and peripheral blood sera of 86 patients with different types of gastrointestinal cancer, from April 2016 to April 2017. The top five types of primary cancer were colorectal (34%), pancreas (28%), stomach (13%), biliary tract (12%), and esophagus (8%). We performed a targeted amplicon exome sequencing for 160 cancer-related genes. The sequencing data was analyzed using an original bioinformatics pipeline within three days, and we identified cancer-specific somatic gene alterations such as SNV (Single Nucleotide Variation), Ins (Insertion)/Del (Deleti...