Detection of unsuspected recurrent lymphoma with fluorodeoxyglucose-positron emission tomographic imaging after...

We performed a fluorodeoxyglucose-positron emission tomographic (FDG-PET) study on a patient who had high-grade lymphoma thought to be in complete remission. The patient underwent the PET study before being considered for high-dose consolidation therapy because he was thought to be at high risk for relapse. The whole-body FDG-PET study revealed an unsuspected hypermetabolic mass in the lower spine that was not visualized on computed tomographic (CT) scanning. The other laboratory values were normal, with the exception of mild lactate dehydrogenase elevation. Two weeks later, the patient developed low back pain, and magnetic resonance imaging showed a 2-cm paraspinal mass at the level of L4. Bone-marrow biopsy confirmed recurrent lymphoma. Remission was not achieved after another chemotherapy regimen. Fluorodeoxyglucose-positron emission tomography can be helpful in the restaging of lymphoma patients after induction chemotherapy and may help to detect early recurrence in selected situations.