Diagnosis and Therapy Control of Ocular Melanoma with 18FDG-PET a Pilot Study

12 patients suspected for choroidal melanoma of the eye were examined in a pilot study with 18FDG-PET. A well visible tumor uptake with significantly elevated Standardized Uptake Values (SUV) for tumors with a prominence > 5 mm was demonstrated. In one patient a non-malignant choroidal lesion (choroidal hemorrhage) could be differentiated. In two patients the simultaneously performed 18FDG-WB-PET showed unknown extraocular metastases, influencing further therapy procedures. In two patients treated with brachytherapy (Iodine-125, Ruthenium-106) a clear response to the radiation was observed. Further studies are needed to clarify the diagnostic value of this method and radiation-dose-effects on 18FDG uptake. As far as we know 18FDG-PET is at the moment the only non-invasive method that provides clinical data concerning the vitality of melanoma cells after radiotherapy. Therefore this method might serve as an important parameter for the effectiveness of therapy and for optimizing radiation protocols.