Follow-up FDG PET/CT in Patients With Non-Hodgkin Lymphoma

Objective: The aim of this study was to evaluate the value of each follow-up PET/CT in the clinical assessment of recurrence as well as determining its impact on management in patients with non-Hodgkin lymphoma (NHL). Patients and Methods: All patients diagnosed with NHL who had at least 1 follow-up PET/CT study, 6 months after primary treatment completion, were included. There were 204 eligible NHL patients with 560 follow-up PET/CT scans. The change in management was recorded after each follow-up PET/CT scan in comparison to the management plan before the study. Results: Among the 560 scans, 388 scans (69.3%) were done without clinical suspicion and 172 scans (30.7%) were done with prior clinical suspicion of recurrence. Follow-up scan results suggested disease in 12.4% of the scans performed without clinical suspicion and ruled out disease in 16.3% scans performed with prior clinical suspicion. The management of NHL patients was changed after 37.8% of follow-up scans with prior clinical suspicion of recurrence and after 8.3% of scans in patients without prior clinical suspicion of recurrence. The management of NHL patients was not changed after 50.6% scans with prior clinical suspicion of recurrence of which 23.3% had no treatment before and after the scan and 27.3% had the same treatment continued before and after the scan. Conclusions: Follow-up FDG PET/CT performed with prior clinical suspicion of recurrence added value to patients with NHL for clinical assessment in 16.3% of the scan times and influenced the management in 37.8% of scan times. The management change was only 8.3% in patients without prior clinical suspicion of recurrence, and hence, surveillance FDG PET/CT in NHL should be avoided.