A 14-year-old girl was examined for a right lateral neck swelling and radiographic mediastinal widening. Biopsy of a right supraclavicular lymph node demonstrated the nodular sclerosing form of Hodgkin's lymphoma. An 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (F18-FDG-PET/CT) study showed several pathological areas of lymph-node uptake in the upper mediastum and right distal tibia. Radiography of the tibia revealed a nonossifying fibroma in the site corresponding to the distal tibial uptake. The PET appearance of benign fibro-osseous lesions may be similar to those of skeletal metastases. Information obtained by the CT component of the PET/CT study and by conventional radiography can be useful in preventing erroneous interpretations of F18-FDG-PET uptake.