825 Assessment of a circulating tumor DNA test for detecting recurrence of Merkel cell carcinoma

Abstract

Approximately 40% of patients with Merkel cell carcinoma (MCC) develop recurrence or metastasis. Early detection can result in better outcomes, and effective surveillance is critical in MCC management. We assessed whether circulating tumor DNA (ctDNA) can accurately detect clinically evident and/or occult MCC. We used the SignateraTM platform in which tumor-specific mutations are identified from archival tumors, and blood is interrogated for those mutations. Since April 2020, we have collected longitudinal ctDNA samples from 95 MCC patients.