Semiquantitative Analysis of Physiological Biodistribution of ⁶⁸Ga-DOTATATE and ⁶⁸Ga-DOTANOC

Abstract

Objective: In this study, we aimed to investigate the physiological biodistribution pattern of 68Ga- DOTATATE and DOTANOC using standardized uptake value (SUV) parameters (maximum and mean) in nontumorous tissues on positron emission tomography/computed tomography (PET/CT) images. Methods: Images of 40 patients (female, n=23 and male, n=17; mean age, 52.50+-15.82 years) who had undergone 68Ga-DOTA labeled (TATE or NOC) PET/CT imaging with the diagnosis of GEPneuroendocrine tumor (NET), non-GEP-NET and thyroid cancer were retrospectively evaluated. SUVmax and SUVmean measurements were performed from areas of physiologic uptake including pituitary gland, parotid and submandibular gland, palatine tonsils, thyroid, lungs, blood pool, thymus, lymph nodes, liver, pancreas (from head, body and tail parts), spleen, stomach, both adrenal gland, kidney, small bowel and colon, bone marrow, prostate, glandular breast tissue and muscle tissue. Results: The highest uptake for 68Ga-DOTATATE and 68Ga-DOTATANOC was noted in the spleen, adrenal, kidney, liver, pituitary gland and head of the pancreas, respectively. Lung, muscle, blood pool, bone marrow, lymph node and breast showed low uptake (SUVmax-mean <2), while moderate uptake was observed in the remaining organs. Conclusion: We think that determination of uptake patterns and range of SUVmax-mean values for both agents in many organs will aid in discriminating between physiologic and pathologic uptake during the interpretation of images.

Keywords

• 68ga-dotatate
• 68ga-dotanoc
• pet/ct
• somatostatin receptor
• physiological biodistribution