Circulating tumour DNA (ctDNA) as a biomarker in metachronous melanoma and colorectal cancer- a case report.

Using cancer-specific mutational targets, we report here for the first time the efficacy of ctDNA to accurately provide a comprehensive outlook of the tumour status of two different cancers within one patient. Thus, ctDNA analysis has a potential clinical utility to delineate clinical information in patients with multiple cancer types.