Prognostic Value of Bone Marrow Metabolism on Pretreatment F-FDG PET/CT in Patients with Metastatic Melanoma Treated with Anti-PD-1 Therapy.

Our purpose was to investigate the prognostic value of F-FDG PET/CT parameters in melanoma patients before beginning therapy with antibodies to the programmed cell death 1 receptor (anti-PD-1). Imaging parameters including SUV, metabolic tumor volume, and the ratio of bone marrow to liver SUV (BLR) were measured from baseline PET/CT in 92 patients before the start of anti-PD-1 therapy. The association with survival and imaging parameters combined with clinical factors was evaluated. Clinical and laboratory data were compared between the high-BLR group (>median) and the low-BLR group (≤median). Multivariate analyses demonstrated that BLR was an independent prognostic factor for progression-free and overall survival ( = 0.017 and = 0.011, respectively). The high-BLR group had higher white blood cell counts and neutrophil counts and a higher level of C-reactive protein than the low-BLR group ( < 0.05). Patients with a high BLR were associated with poor progression-free and overall survival, potentially explained by evidence of systemic inflammation known to be associated with immunosuppression.