High basal maximal standardized uptake value (Suvmax) in follicular lymphoma identifies patients with a low risk of long-term relapse

Background: Despite that the unfavorable prognostic role of a high Total Metabolic Tumor Volume (TMTV) in Follicular Lymphoma has been demonstrated, the role of SUVmax alone at baseline PET/CT could have a different prognostic role. Patients and Methods: We performed a retrospective observational monocentric cohort study. All patients affected by FL who underwent a basal PET/CT were included. Two subgroups were identified and compared in terms of PFS and OS: (A) Basal SUVmax ≤ 6; and (B) Basal SUVmax > 6. Results: Ninety-four patients were included, 34 in group A (36.2%) and 60 in group B (63.8%). The PFS at two years was comparable in the two groups (97%). The five-year PFS was 73.5% for group A and 95% for group B (p 0.005). The five-year PFS in the whole cohort was 87.5%. A clear advantage was confirmed in group A in the absence of other risk factors. Patients with SUVmax ≤ 6 and no risk factors showed a 5-year PFS of 73% against 83% for patients with SUVmax > 6 and at least two risk factors. Conclusion: A high FDG uptake favorably correlated with PFS. A low basal SUVmax reflected a higher rate of late relapse requiring a prolonged follow-up. The basal SUVmax is an approachable parameter with prognostic implications.