Diffuse Subcutaneous and Muscular Langerhans Cell Histiocytosis on FDG PET/CT

: Langerhans cell histiocytosis (LCH) is a rare cancer that represents a set of pathological outcomes due to the abnormal proliferation of Langerhans cells, which is more commonly seen in pediatric patients. FDG PET/CT findings of an adult LCH patient with extensive infiltration in the subcutaneous tissue and muscles was described in this case.