During follow‐up, 13 patients in the BRAF monotherapy arm had HF (6‐month rate of 1.9% (CI: 1.0–3.9%)) compared to 5 patients in the BRAF/MEK combination arm (6‐month rate of 6.9% (CI: 2.8–16.7%); Figure 3B). Here, MAP2K7 is linked to hydrops fetalis.