Table 3. Overview of tracer uptake in normal tissues and tumor lesions before and after SSAs treatment.

Author [year]	Liver	Spleen	Kidney	Adrenal gland	Thyroid	Pituitary gland	Parotid gland	Bone	Tumor	Tumor-to-liver/background ratio
Jahn [2021]† (33)	↓	↓	NS	–	–	–	–	NS	NS	–
Gålne [2019] (24)	↓	–	–	–	–	–	–	–	NS	The tumor-to-liver ratio was higher after treatment initiation with LA SSA and the tumor lesions in the liver were better visualized
Li [2019]‡ (32)	↓	NS	NS	NS	–	–	–	↓	NS	–
Aalbersberg [2019] (23)	↓	↓	NS	NS	↓	NS	NS	NS	↑	The tumor-to-liver ratio for SUVmax increased after lanreotide injection in all lesions
Cherk [2018] (31)	↓	↓	–	NS	↓	↑	NS	–	↑§	Metastatic lesion uptake and lesion-to-liver SUVmax ratio increased in 82% of lesions following SSA therapy
Ayati [2018] (22)	↓	↓	–	NS	↓	NS	–	–	NS	–
Haug [2011] (30)	↓	↓	NS	NS	–	NS	–	–	NS	–
Janson [1999] (29)	–	–	–	–	–	–	–	–	–	The tumor-to-background ratio had an average increase in the ratio of 50%, while the spleen-to-background ratio decreased significantly (the average reduction ratio was 55%)
Dörr [1993] (28)	↓	↓	↓	–	–	–	–	–	↑	The tumor-to-liver ratio improved markedly

^†, the time interval was 7 hours; ^‡, the individual measurement of tracer uptake was target-to-muscle ratio; ^§, 61% of metastatic lesions had an increase in SUVmax following SSA therapy. ↓, decrease; ↑, increase; –, not available; SSAs, somatostatin analogs; NS, no significance; SUVmax, maximum standardized uptake value.