Prognostic Significance of the Imaging Parameters of Adipose Tissue and Bone Marrow on F-18 Fluorodeoxyglucose PET/CT in Patients with Malignant Melanoma

Abstract

Purpose Fluorodeoxyglucose (FDG) uptake of bone marrow (BM) and adipose tissue is known to reflect systemic inflammatory response to cancer cell. The objective of this study was to evaluate the prognostic value of F-18 FDG uptake of BM and determine characteristics of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) on PET/CT images in malignant melanoma. Materials and Methods We retrospectively reviewed 33 patients histopathologically diagnosed with malignant melanoma via FDG PET/CT staging. BM-to-liver uptake ratio (BLR), volume of VAT and SAT, CT Hounsfield unit (HU), and mean of standardized uptake value (SUVmean) of VAT and SAT on PET/CT were measured and prognostic values of these parameters for prediction of disease progression-free survival (DPFS) were evaluated. Results Patients with stage III–IV melanoma had higher CT HU and SUVmean for SAT and VAT but lower volume of VAT compared with patients at stage I–II (p < 0.05). Survival analysis, patients with high CT HU of VAT and SAT, high SUVmean of VAT and SAT, and high BLR showed worse DPFS (all p < 0.05), indicating significant association. However, volume of SAT or VAT failed to show significant association with DPFS (p > 0.05). Conclusion CT HU, SUVmean of SAT and VAT, and BLR provide prognostic information for DPFS in malignant melanoma. Received December 18, 2018 Revised March 25, 2019 Accepted June 6, 2019