A pilot study on the biodistribution pattern of 68Ga-DOTA-TATE in normal organs of adults / 中华核医学与分子影像杂志

ABSTRACT

Objective To retrospectively study the biodistribution of 68Ga-DOTA-TATE as a SSTR imaging agent in human subjects.Methods A total of 106 patients with suspected disease were enrolled in this study.All patients were histologically proven for having either a single tumor ＜2 cm or without evidence of tumor during follow-up.Patients underwent PET/CT whole-body scan 17-100 min after intravenous injection of 55.2-220.0 MBq 68Ga-DOTA-TATE.ROI was drawn for measuring SUV of tracer-avid pathologies.One-way analysis of variance and two-sample t test were used for statistical analysis.Results High 68Ga-DOTA-TATE avidity was found in pituitary,with SUVmax of 4.00± 1.21.Tracer was excreted mainly through urinary system resulting in highest uptake in the urinary tracts.The SUVmax of kidney cortex was 19.01 ± 5.45.Mediastinal blood pool and liver SUVmax were 0.93±0.33 and 7.69±2.26,respectively.Mild uptake of 68Ga-DOTA-TATE was found in the brain,cerebellum,lung and muscle,all lower than that of mediastinal blood pool.Moderate accumulation of 68 Ga-DOTA-TATE (close to or slightly higher than liver) was found in adrenal gland and spleen,with SUVmax 7.61 ± 3.42 and 8.63± 2.31,respectively.Other organs (pituitary,salivary gland,thyroid,pancreas,small intestine,colon,uterus,prostate and bone) showed tracer uptake in the range between those of mediastinal blood pool and liver.68Ga-DOTA-TATE distribution in pancreas was not uniform.Nine patients had focal accumulation in the uncinate process of pancreas with highest SUVm~ up to 8.48.However,the SUVmax and SUV in the rest of pancreas (head,neck,body and tail) showed insignificant difference (F values0.703,0.563,both P＞0.05).68Ga-DOTA-TATE uptake in each organ reached equilibrium quickly after injection but with slight increase over time.The changes in SUV,however,showed insignificant difference among organs,including different parts of pancreas (t valuesfrom -0.09 to 1.75,from-1.70 to-0.42,respectively,all P＞0.05).Conclusions The biodistribution of 68Ga-DOTA-TATE reaches equilibrium shortly after intravenous administration and is stably maintained.The biodistribution activities are organ-specific,and characteristic to that of SSTR concentration.