CT and MR imaging of solitary extramedullary plasmacytoma of the nasal tract.

BACKGROUND AND PURPOSE: Solitary extramedullary plasmacytoma (SEP) is rare. The purpose of this study was to determine the CT and MR imaging features of SEP of the nasal tract. METHODS: We retrospectively reviewed three CT and two MR images of three histologically proved cases in two men and one woman aged 43-66 years. RESULTS: The plasmacytomas predominantly involved the nasopharynx in two cases and the nasal cavity in one. Two of the tumors were bulky solid masses, whereas the third showed infiltrative features. They were predominantly masses or infiltrative lesions with soft-tissue attenuation on CT scans. The lesions were isointense and hyperintense on T1- and T2-weighted MR images, respectively. The tumors revealed moderate-to-marked contrast enhancement and may have been associated with lytic bone destruction. CONCLUSION: The imaging features of SEP are nonspecific. However, this entity should be included in the differential diagnosis of tumors in the nasopharynx and nasal cavity.

Current paradigm of the 18-kDa translocator protein (TSPO) as a molecular target for PET imaging in neuroinflammation and neurodegenerative diseases.

Neuroinflammation is a process characterised by drastic changes in microglial morphology and by marked upregulation of the 18-kDa translocator protein (TSPO) on the mitochondria. The continual increase in incidence of neuroinflammation and neurodegenerative diseases poses a major health issue in many countries, requiring more innovative diagnostic and monitoring tools. TSPO expression may constitute a biomarker for brain inflammation that could be monitored by using TSPO tracers as neuroimaging agents. From medical imaging perspectives, this review focuses on the current concepts related to the TSPO, and discusses briefly on the status of its PET imaging related to neuroinflammation and neurodegenerative diseases in humans.