Utilization of PET imaging in differential diagnostics between a tumefactive multiple sclerosis lesion and low-grade glioma.

We present a case where a 30-year-old man with a history of combined MS and Charcot-Marie-Tooth (CMT I) disease was additionally diagnosed and treated for grade II glioma (astrocytoma). Tumefactive MS and gliomas are sometimes difficult to distinguish from one another based on conventional magnetic resonance imaging (MRI). In our case, positron emission tomography (PET) scans with(11)C-methionine ((11)C-MET) and (11)C-PK11195 radioligands were performed to aid in differential diagnostics. The diagnosis was confirmed finally by brain biopsy. The usefulness of PET imaging in differential diagnostics between tumefactive MS and glioma is discussed.