Figure 2: FDG PET/CT imaging of a patient with a stage 2 FL in relapse, treated by RAIT in a phase I/II protocol using fractioned 90Y-epratuzumab with a partial metabolic response at 6 weeks and 3 months after RIT and who experienced relapse 6 months after RAIT. Figure 1(a) shows the FDG PET/CT image before RAIT with accumulation of FDG in lomboaortic, iliac, and inguinal nodes. Figures 1(b) and 1(c) show the FDG PET/CT images realised 6 weeks and 3 months after RIT, showing a residual uptake of FDG in left iliac nodes. Figure 1(d) shows the FDG-PET images realised 6 months after RIT with pathologic accumulation of FDG in lombo-aortic, iliac and inguinal nodes confirming clinical suspicion of relapse.