Background: Combined PET/CT using 18F could be very effective with the minimal hazards as well as false findings compared to the use one of these components alone in assessment of lymphoma. The purpose of this study was to review the usefulness of FDG PET/CT in diagnosis and staging of lymphoma, assessment of response to therapy, follow up and assessment of remissions and relapses among patients who had extranodal lymphoma.

Methods: This cross-sectional study involved 36 patients who had pathologically confirmed lymphoma who underwent PET/CT study. A PET/CT in-line system was used to collect all of the data (General Electric PET CT Discovery). Prior to conducting a diagnostic enhanced whole-body CT scan, we conducted a low-dose enhanced CT scan, then a whole-body PET study.

Results: The study compared the efficacy of contrast-enhanced CT and PET/CT in detecting lymphoma manifestations in 36 patients. PET/CT showed high sensitivity (100%) in detecting lymph node involvement and other extranodal manifestations, with varying specificity. Treatment response was evaluated using IHP and visual assessment based on the Déauville Criteria, showing a high level of agreement between the two methods.

Conclusion: One promising oncologic imaging modality that could play a significant role in lymphoma care is a PET/CT combination that using 18F-FDG. In the early interim and after treatment ended, response assessments based on the Deauville criteria seemed to agree with IHP classifications to a reasonable degree.