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

Objective(s): 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. conclusion: 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.