Two patients with different histologic subtypes of MDB were referred for F-DOPA PET to define the extent and metabolic degree of their diseases. The patients had a newly diagnosed large-cell/anaplastic MDB and a fourth relapse of classic MDB, respectively. F-DOPA PET was unremarkable in the first case; F-DOPA uptake was low in the second patient with the tumor/background ratio as high as 1.29. Comparison was made with magnetic resonance imaging, which showed fluid-attenuated inversion recovery positive diseases. Aggressive tumor growth was shown in the clinical course of both patients.
The 2 cases reported here suggest that sensitivity of F-DOPA PET in MDB can be low. However, more comprehensive data are needed to conclude on the overall accuracy of F-DOPA PET in MDB.