Fig. 1: ctDNA quantification in melanoma patients at the time of progressive disease on systemic therapy.

a Plasma ctDNA levels (copies/mL of plasma) in melanoma samples (N = 108), stratified by mutation status. Red dots identify patients with the intracranial disease only. b M1d cases were further subdivided into those with extracranial (IC + EC) and those with brain-only metastases (IC only). Percentages denote the frequency of patients with detectable ctDNA. The geometric mean of ctDNA concentrations is indicated for each group by a line.