Finally, BRAF p.Val600Glu AF in ctDNA from patient #62 increased during first-line therapy with BRAF+MEKi (from 12% pre-treatment to 39% at the disease progression), as well as the total cfDNA level (from 53 ng/mL to 101.3 ng/mL) (Figure 1C). The gene discussed is BRAF; the disease is atrial fibrillation.