Prognostic significance of interim PET/CT response for the treatment of advanced-stage marginal zone lymphoma in the post-rituximab era

There are still controversies about the use of interim positron emission tomography/computed tomography (PET/CT) in indolent non-Hodgkin lymphoma due to the variable fluorodeoxyglucose (FDG) avidity. Therefore, this study aimed to evaluate the roles of interim PET/CT in marginal zone lymphoma (MZL), a representative indolent lymphoma. We analyzed the data of 146 MZL patients. All were treated with rituximab-containing immunochemotherapy. Interim PET/CT scan was performed after 2–3 cycles of therapy, and the response was assessed using the Deauville 5-point scales (5-PS) and a semi-quantitative assessment using the SUVmax reduction rate (ΔSUVmax). Progression-free survival (PFS) was well stratified according to a visual assessment of interim PET/CT using 5-PS (p p = 0.031). The interim PET/CT response based on the 5-PS is useful for predicting PFS of patients with MZL in the post-rituximab era.