Neurotensin receptors: a new marker for human ductal pancreatic adenocarcinoma

BACKGROUND/AIMS: New imaging possibilities for early diagnosis of the devastating exocrine pancreatic adenocarcinomas would be highly welcome. Recently, pancreatic neuroendocrine tumours have been successfully visualised in vivo on the basis of their high density of receptors for the regulatory peptide somatostatin. Unfortunately, exocrine pancreatic tumours do not express sufficient amounts of somatostatin receptors. Therefore over-expression of other regulatory peptide receptors in these tumours needs to be found. METHODS: Receptors for the regulatory peptide neurotensin were evaluated in vitro by receptor autoradiography in 24 ductal pancreatic adenocarcinomas, 20 endocrine pancreatic cancers, 18 cases of chronic pancreatitis, and 10 normal pancreatic glands. RESULTS: Some 75% of all ductal pancreatic adenocarcinomas, most of them differentiated, were neurotensin receptor positive, whereas endocrine pancreatic cancers did not express neurotensin receptors. No neurotensin receptors were found in chronic pancreatitis or normal pancreatic tissues, including pancreatic acini, ducts, and islets. CONCLUSIONS: The selective and high expression of neurotensin receptors in ductal pancreatic adenocarcinomas could form the molecular basis for potential clinical applications, such as in vivo neurotensin receptor scintigraphy for early tumour diagnosis, radiotherapy with radiolabelled neurotensin analogues, and chemotherapy with neurotensin receptor antagonists.