Mediastinal teratoma with metastatic lymph node: misleading normal thymic uptake of F-18 FDG.

摘要

F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) typically demonstrates prominent thymus uptake in normal children and young adults. A 12-year-old girl presenting with back pain and respiratory discomfort underwent an FDG PET/CT examination that demonstrated an anterior mediastinal mass with relatively low FDG uptake and an apparently separate FDG-positive nodular lesion superior to the larger mass. Surgical excision demonstrated a larger mature teratoma mass with a smaller thymic tissue nodule connected to the tumor with hourglass bridging.