Comprehensive genomic profiling for chemotherapy-naïve advanced gastrointestinal malignancies.

Abstract

832 Background: From June, 2019, two comprehensive genomic profiling (CGP) assays, "FoundationOne CDx" and “OncoGuide NCC Oncopanel”, were reimbursed by the national insurance system in Japan for patients who were refractory to standard chemotherapy. However, their clinical utility for chemotherapy-naïve cancer patients is unknown. Methods: We conducted a single institutional prospective observational study to evaluate the clinical utility of FoundationOne CDx assay (Cambridge, MA, USA) for the patients with chemotherapy-naïve advanced gastrointestinal malignancies. Patients with adequate H.E. sample were registered in this study. Primary outcome was the detection rate of at least one actionable/druggable cancer genomic alterations. The evidence levels were classified according to clinical practice guidance for next-generation sequencing in cancer diagnosis and treatment (Edition 1.0) (Sunami K. Cancer Sci. 2018). Results: From October 2018 to June 2019, a total of 238 patients were screened and the following 158 patients were registered: colorectal cancer (n = 60), gastric cancer (n = 19), esophageal cancer (n = 23), pancreatic cancer (n = 30), biliary tract cancer (n = 11), rare gastrointestinal malignancies (n = 15). The CGP data were obtained for 113 patients . Median turn-around time was 14 days (range 10-247 days). Actionable/druggable cancer genomic alterations were observed in 113 patients (100%)/ 65 patients (57.5%), respectively. Clinically relevant biomarkers and genomic alterations were identified in 22 patients (19.5%); BRCA2 (n = 4), ERBB2 (n = 4) , BRAF (n = 3) , EGFR (n = 3), FGFR2 (n = 2), MET (n = 2), NTRK (n = 2) , MSI-H (n = 2 ), TMB-high (n = 2), ALK (n = 1) , KIT (n = 1) and ROS1 (n = 1). Of note, novel biomarkers such as ROS1- GOPC fusion and PALB2 rearrangement were obtained in the patients with esophageal squamous cell carcinoma. Conclusions: This is the first study to evaluate the clinical utility of CGP in patient with chemotherapy-naïve advanced gastrointestinal malignancies. Our result indicated that CGP might provide a chance of potentially effective drugs as a novel approach in precision cancer medicine. Clinical trial information: UMIN000034830.