A case of cervical paraganglioma: usefulness of FDG PET imaging and a possibility of rare origination.

Cervical paragangliomas are rare tumors derived from neural crest cells. Anatomic imaging techniques rely upon the characteristic spatial relations and the high vascularity of this tumor. Results of computed tomography (CT), magnetic resonance imaging (MRI), and arteriography initially led us to the preoperative diagnosis of cervical paraganglioma. In our case, 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET), a type of functional imaging, was also carried out and demonstrated abnormally increased tracer uptake; this approach was thus successful for visualizing paraganglioma. FDG PET imaging may be useful in the detection of benign paraganglioma. On surgical exploration of the neck, the tumor was found to arise from the vagus nerve, whereas the hypoglossal nerve was encompassed by the tumor in its upper portion. The intraoperative findings suggested the possibility that the tumor had arisen from the hypoglossal nerve.