F-18 FDG PET/CT evaluation of sacrococcygeal chordoma.

Chordoma is a rare malignant bone tumor derived from notochordal rests, and the most common site is the sacrococcygeal region. A 52-year-old woman presented with a sacrococcygeal chordoma detected on F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT). The F-18 FDG PET/CT showed a large destructive mass that arose anteriorly in the sacrococcygeal region and heterogeneously increased FDG uptake within the mass was observed. After surgery, histology confirmed the presence of a sacrococcygeal chordoma. The physician should take chordoma into consideration if there is a large osteolytic mass with hypermetabolism in the sacral region on FDG PET/CT.