Brain Tumours

METABOLIC IMAGING PET [11C]Methionine (MET)

• The highest uptake is observed in anaplastic oligodendrogliomas WHO grade III • LGG are better detected by aminoacid tracers due to increased uptake in the absence of blood- brain barrier damage • LGG: useful for differentiation from nonntumorous lesions, detection of recurrences, indication of progressing disease • Can differentiate better between Recurrent tumour and Radiation Necrosis with high sensitivity and specificity (~75%): necrosis and glioses after therapy show a reduction of ammoniated uptake in contrast to recurrent and residual tumour growth . • Deactivation of aminoacid transport is a early sign of response to chemotherapy (Galldicks N et al Mol Imaging 2010). PET responders with a decrease of tumour brain/ratio of >10% had a significant longer TTP and OS than patient with increase tracer uptake after RT and CHT in GBM.