We performed a single-center study comprised of 31 consecutive patients with lymphoma within 3 months after completion of conventional initial therapy or after salvage therapy with high-dose chemotherapy. PET studies were performed by using fluorine-18-fluorodeoxyglucose (FDG) and a hybrid PET camera with triple-head coincidence imaging capability. The long-term follow-up data (at least 12 months, median 20 months) were extracted from the patients’ medical files. Fifteen patients were FDG-negative, 12 were positive, and in 4 patients, only slightly increased FDG uptake was observed (equivocal findings, 2 relapsed). Besides all shortcomings of coincidence PET, we found this hybrid PET methodology good enough for reliable prognosis in follow up of our patients, especially in those without pathologic FDG uptake.