PET/CT for therapy response assessment in lymphoma.

PET with (18)F-FDG is a standard staging procedure for most lymphoma subtypes. Performed during and after therapy for Hodgkin lymphoma (HL) and aggressive non-Hodgkin lymphoma (NHL), (18)F-FDG PET results have a high prognostic value and correlate with survival. (18)F-FDG PET has been incorporated into revised response criteria for aggressive lymphomas, and several ongoing trials are under way to investigate the value of treatment adaptation based on early (18)F-FDG PET results for HL and aggressive NHL. There is little evidence to support the use of (18)F-FDG PET for monitoring of the treatment of indolent lymphomas and for routine use in the surveillance setting. So that trial results can be compared and translated easily into clinical practice, uniform and evidence-based guidelines for the interpretation and reporting of response monitoring scans are warranted. Because it is still not proven that the use of interim (18)F-FDG PET can improve patient outcomes, we recommend examination of the use of (18)F-FDG PET for response monitoring in appropriately designed clinical trials.