BRAF and familial atrioventricular septal defect: Bone scintigraphy of ECD patients may show pathological uptake in long bones due to cortical osteosclerosis [2]; positron emission tomography-computed tomography (PET-CT) has advantages in showing the extent and activity of ECD lesions, and the therapeutic response to BRAF inhibitor, MEK inhibitor and interferon-α [3, 5–9]; computed tomography (CT) and magnetic resonance imaging (MRI) may help image-guided biopsy for ECD diagnosis [1].