Background: Background activity on fluorine-18-fluorodeoxyglucose (18F-
FDG) positron emission tomography/computed tomography (PET/CT) is 
frequently used as a reference to evaluate how patients respond to tumor 
therapy. The purpose of this research was to assess how biological and technical 
factors alters the uptake of the liver and mediastinal blood pool (MBP) in 
lymphoma. 
Methods: This retrospective study enrolled 62 lymphoma patients underwent 
initial 18F-FDG PET/CT examinations before receiving any therapy, SUV 
metrics included SUVmax, SUVmean and SUVpeak for the pathologically 
proved lesion as well as of the liver and the MBP.
Results: The study included 62 patients, 35 had HL and 27 had NHL (47 males 
and 15 females, with a mean age of 27.82 ± 23.33 years), we found that the 
duration of uptake, followed by weight were the most important predictors of 
SUVmax as well as SUVmean, and SUVpeak of the lesion. Meanwhile, weight 
was one of the most significant indicators of SUV values of the liver, followed 
by age. On the other hand, weight was one of the most significant indicators of 
SUVmax and SUVpeak of the mediastinal blood pool. However, Blood glucose 
level followed by weight with a slight difference were the most important 
predictors of SUVmean of the mediastinal blood pool.
Conclusion: biological and procedural factors are essential factors that cause 
changes in the blood pool and liver SUVs. The so-called reference organs i.e. 
the MBP and liver, are affected with variation in weight, age, and blood glucose. 
Our study showed that in all liver and mediastinal blood pool measurements, 
weight had the upper hand.