We investigated clinical characteristics of patients with extremely increased or decreased physiologic 18F-FDG uptake of the liver and their prognosis.
One thousand four hundred eighty-seven PET/CT scans of patients with known or suspected malignancy were retrospectively analyzed. A spherical volume of interest (3 cm in diameter) was set on the right lobe of the liver to calculate the SUVmean. Scans with extremely high (SUVmean >97.5th percentile) and low (SUVmean <2.5th percentile) FDG uptake in the liver were evaluated. Physical and laboratory data among a control group (n = 30), the extremely high liver uptake group (HG, n = 36), and the extremely low liver uptake group (LG, n = 36) were compared. Overall survival (OS) of the 3 groups was also compared.
Body weight and body mass index in the HG (SUVmean ≥3.04) were significantly higher than those in the control group. The LG cases (SUVmean ≤1.78) had anemia, impaired liver function, and systemic inflammation. They were also in a poor nutritional state. The characteristics of LG cases had many things in common with those of cachectic patients. Indeed, 36.1% of LG cases met the diagnostic criteria for cachexia. Moreover, in LG cases with viable and/or recurrent malignant lesions on FDG PET, the proportion of cachexia increased by 52.6%. The OS of LG cases (median, 33 months) was significantly worse than that of controls and HG cases.
Our data indicate that cancer patients with extremely decreased liver FDG uptake were likely to have cancer cachexia and a lower OS.
From the *Department of Radiology, Shiga General Hospital
†Division of PET Imaging, Shiga Medical Center Research Institute, Moriyama
‡Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto
§Department of Molecular Imaging and Theranostics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology (QST), Chiba, Japan.
Received for publication February 14, 2019; revision accepted April 28, 2019.
Conflicts of interest and sources of funding: none declared.
Correspondence to: Ryusuke Nakamoto, MD, PhD, Shiga General Hospital, 5-4-30, Moriyama, Moriyama, Shiga 524-8524, Japan. E-mail: firstname.lastname@example.org.
Online date: June 3, 2019