Purpose The purpose of this study was to evaluate the prognosticvalue of metabolic tumor volume (MTV) measured by 18F-fluorodeoxyglucose positron emission tomographycomputed tomography (FDG-PET/CT) in patients with diffuse large B-cell lymphoma (DLBCL) treated with rituximabcontaining immunochemotherapy.
Methods Patients with newly diagnosed DLBCL who underwent pre-treatment torso FDG-PET/CT scan taken within 10 days before treatment were included. MTV was defined as the volume of hypermetabolic tissue with a standardized uptakevalue (SUV) greater than a threshold value of 2.5 and calculated using volume viewer software. Association of MTV with patient characteristics and survival were compared.
Results A total of 96 patients were evaluated. During a median follow-up period of 27.8months, 3-year event-free survival(EFS) and overall survival was 69.5 % and 72.9 %, respectively. The Ann Arbor staging showed a limitation of prognosis because there was no difference of EFS between patients with Ann Arbor stage Ⅱ and those with stage Ⅲ. On thecontrary, among patients with Ann Arbor stage Ⅱ or Ⅲ disease(n=53), the higher MTV group showed significantly inferior EFS compared with the lower MTV group.
Conclusions In the current study, we identified the pretreatment MTV measured by FDG-PET/CT as a potential predictor of survival in patients with DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone (R-CHOP), at least in Ann Arbor stage Ⅱ and Ⅲ disease.