title: Prognostic Value of FDG-PET, Based on the Revised Response Criteria, in Patients with Malignant Lymphoma: A Comparison with CT/MRI Evaluations, Based on the International Working Group/Cotswolds Meeting Criteria.
abstract: OBJECTIVE
  Post-treatment evaluations by CT/MRI (based on the International Working Group/Cotswolds meeting guidelines) and PET (based on Revised Response Criteria), were examined in terms of progression-free survival (PFS) in patients with malignant lymphoma (ML).
  
  
  METHODS
  79 patients, undergoing CT/MRI for the examination of suspected lesions and whole-body PET/CT before and after therapy, were included in the study during April 2007-January 2013. The relationship between post-treatment evaluations (CT/MRI and PET) and PFS during the follow-up period was examined, using Kaplan-Meier survival analysis. The patients were grouped according to the histological type into Hodgkin's lymphoma (HL), diffuse large B-cell lymphoma (DLBCL), and other histological types. The association between post-treatment evaluations (PET or PET combined with CT/MRI) and PFS was examined separately. Moreover, the relationship between disease recurrence and serum soluble interleukin-2 receptor, lactic dehydrogenase, and C-reactive protein levels was evaluated before and after the treatment.
  
  
  RESULTS
  Patients with incomplete remission on both CT/MRI and PET had a significantly shorter PFS, compared to patients with complete remission on both CT/MRI and PET and those exhibiting incomplete remission on CT/MRI and complete remission on PET (P<0.001). Post-treatment PET evaluations were strongly correlated with patient outcomes in cases with HL or DLBCL (P<0.01) and other histological types (P<0.001). In patients with HL or DLBCL, incomplete remission on both CT/MRI and PET was associated with a significantly shorter PFS, compared to patients with complete remission on both CT/MRI and PET (P<0.05) and those showing incomplete remission on CT/MRI and complete remission on PET (P<0.01). In patients with other histological types, incomplete remission on both CT/MRI and PET was associated with a significantly shorter PFS, compared to cases with complete remission on both CT/MRI and PET (P<0.001). None of the serum parameters differed significantly between recurrent and non-recurrent cases.
  
  
  CONCLUSIONS
  Post-treatment PET evaluations were well correlated with the outcomes of patients with ML, exhibiting FDG uptake. Among patients with HL or DLBCL, a post-treatment complete remission on PET was predictive of a relatively long PFS. For predicting the prognosis of patients with other histological types, a combination of CT/MRI and PET, rather than PET alone, is recommended.
authors.affiliation: Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Kayako
authors.initials: K
authors.lastname: Isohashi
authors.affiliation: Department of Radiology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Tatsumi
authors.affiliation: Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kato
authors.affiliation: Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Fukushima
authors.affiliation: Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Maeda
authors.affiliation: Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Watabe
authors.affiliation: Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Eku
authors.initials: E
authors.lastname: Shimosegawa
authors.affiliation: Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yuzuru
authors.initials: Y
authors.lastname: Kanakura
authors.affiliation: Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka, Japan; Department of Radiology, Osaka University Graduate School of Medicine, Osaka, Japan; Immunology Frontier Research Center, Osaka University, Osaka, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Hatazawa
keywords: CT; FDG-PET; MRI; Malignant Lymphoma; Prognosis