[Immunoscintigraphy of choroid melanoma using monoclonal antibodies]

A prospective pilot study on immunoscintigraphy with monoclonal antibody fragments against cutaneous melanoma (MoAb 225.28S) was performed in 17 patients with a clinical diagnosis of choroidal melanoma. Monoclonal antibodies against melanoma associated antigen were labelled with 740 mBq (20 MCi) of the radionuclide 99mTc and injected intravenously. Images were made with a gamma camera 6 hours after injection. With a double pinhole collimator radioactivity was counted thrice in both eyes 6 hours after injection. In 6 out of 17 patients (35.3%) the melanoma could be imaged with the gamma camera. With the double pinhole collimator a significantly higher activity was measured in the melanomatous eye in 13 out of 17 patients (76.5%). In four patients a false negative result was obtained. Considering these results immunoscintigraphy may be valuable in ocular melanoma diagnostics but its specific value still has to be assessed.