Dr. Shirasu on the Utilization of ctDNA Testing in CRC

Hiromichi Shirasu, MD, senior staff member, Division of Clinical Oncology, Shizuoka Cancer Center, Shizuoka, Japan, discusses the utilization of circulating tumor DNA (ctDNA) testing in colorectal cancer (CRC). 

The GALAXY trial (UMIN000039205), part of the CIRCULATE-Japan project, is an ongoingstudy monitoring ctDNA in patients with resectable CRC, Shirasu says. The Signatera™ assay is a novel, patient-specific, custom-built ctDNA test that detects minimal residual disease in the plasma, Shirasu explains. The assay tests for 16 patient-specific, somatic, single-nucleotide variants, Shirasu continues.

Via whole-exome sequencing of the tumor tissue, the assay is highly specific and sensitive based on a variant-allele frequency of 0.01%, Shirasu concludes.