Positron Emission Tomography/Computed Tomography before Treatment as a Predictor of 90Y-Ibritumomab Tiuxetan Response

[Introduction] Radioimmunotherapy (RIT) has appeared as one of the most effective treatment options for patients with relapsed or resistant indolent Non-Hodgkin's lymphoma (NHL). Although the high efficacy of RIT has been already well established, long-term toxicity, high cost, and limited availability are still potential drawbacks in the clinical setting. Therefore, a predictor of favorable outcome before RIT is needed for patient selection. 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has been widely used and recommended as a main imaging modality in FDG-avid lymphoma. However, the role of FDG-PET/CT before treatment as a RIT response predictor has yet to be confirmed. The purpose of this study was to evaluate FDG-PET/CT before treatments as a predictor of 90Y-Ibritumomab tiuxetan treatment. [Patients] A retrospective study was performed in twenty patients who underwent 90Y-Ibritumomab tiuxetan in our institution for relapsed or resistant indolent NHL.