Clinical progress and distribution of BRAF^V600E alleles in PBMC and sorted cell fractions. (A) Patients 1 and 2 treated with conventional chemotherapy. (B) Patients 3 to 6 treated with inhibitors. Pie charts depict the distribution of mutated cells as a proportion of all mutated cells detected in blood. Each chart is aligned as closely as possible to the corresponding time point. Blue symbols at the top indicate chemotherapy cycles; red bar indicates MAPK inhibitor. Clinical scores and mutation analyses over time are shown in rows (top to bottom). Filled gray areas indicate negative results below 0.0001. Disease Activity Score (DAS) was measured according to Donadieu et al¹⁷; BRAF^V600E mutation fraction measured in total PBMC (filled symbols and lines) and plasma cell-free DNA (open symbols and broken line); BRAF^V600E mutation fraction measured in sorted subsets; and mutated cells per μL in sorted subsets. Asterisks indicate rapid disease reactivation when treatment was suspended. Red line indicates classical CD14⁺ monocytes; orange line indicates CD16⁺ nonclassical monocytes; blue line indicates CD1c⁺ myeloid DC; and green line indicates CD3⁺ T cells. VBL/pred, vinblastine and prednisone; VCR/pred/Ara-C, vincristine, prednisone, and cytarabine; 2CdA/Ara-C, cladribine and cytrarabine; 6-MP/MTX: 6-mercaptopurine and methotrexate maintenance.