Preclinical Evaluation of 68Ga-DOTA-NT-20.3: A Promising PET Imaging Probe To Discriminate Human Pancreatic Ductal Adenocarcinoma from Pancreatitis

Neurotensin receptor 1(NTSR1) is overexpressed in human pancreatic ductal adenocarcinoma (PDAC). Specific noninvasive positron-emission tomography (PET) imaging probes may improve the diagnostic accuracy and the monitoring of therapy for patients with PDAC. Here, we report the use of the 68Ga-labeled neurotensin(NTS) analogue DOTA-NT-20.3 to image human PDAC in animal models and to discriminate tumors from pancreatitis. In addition to the preclinical study, two tissue microarrayslides, constructed by small core biopsies (2–5) from standard paraffin-embedded tumor tissues, were used to confirm the high (78%) positivity rate of NTSR1 expression in human PDAC. PET imaging, biodistribution, blocking, and histology studies were performed in subcutaneous AsPC-1 pancreatic tumor-bearing mice. 68Ga- DOTA-NT-20.3 PET images showed rapid tumor uptake and high contrast between the tumor and background with a fast blood clearance and a moderate accumulation in the kidneys. Ex vivo biodistributionshowed low uptake ...