Influence of fever on 18F-FDG PET/CT in vivo: Utilizing a quantitative parameter SUL.

INTRODUCTION

Fever can affect the identification and efficacy evaluation of tumors on the 18F-FDG PET/CT, and this effect can be reduced by referring to normal tissue metabolism. The aim of the study was to analyze the influence of fever on glucose metabolism in the mediastinal blood pool, liver, spleen, and bone marrow utilizing PET/CT quantitative parameter SUV normalized by lean body mass (SUL).

MATERIALS AND

METHODS

30 patients with fever of unknown origin and 24 patients for tumor screening with normal body temperature within 3 weeks, who underwent 18F-FDG PET/CT in our department, were analyzed retrospectively. The SULmax and SULmean of the mediastinal blood pool, liver, spleen, and bone marrow were respectively measured in the two groups, and the differences between the two groups were compared by independent sample t test or Wilcoxon-Mann-Whitney test.

RESULTS

The SULmax and SULmean of the liver in the fever group were lower than those in the control group (p = 0.001, 0.013). The SULmax and SULmean of spleen and bone marrow in the fever group were higher than in the control group (all p < 0.05). The SULmax of the mediastinal blood pool in the fever group was lower than that in the control group (p = 0.007), but there was no significant difference in SULmean of the mediastinal between the fever group and the control group (t = 1.181, p = 0.221).

CONCLUSION

The fever can affect the glucose metabolism in internal organs. But there was no significant difference in the SULmean of mediastinal blood pool. Perhaps the SULmean of the blood pool can be invoked as a calibration parameter in the evaluation of efficacy in tumor patients with fever.