Neurotensinlike immunoreactivity in plasma and tumor tissue from patients with endocrine tumors of the pancreas and gut.
Nine of 34 (26%) consecutive patients with different endocrine gastrointestinal tumors had increased levels of plasma neurotensinlike immunoreactivity in the fasting state. This was the case in 6 of 18 (33%) patients with endocrine pancreatic tumors and in 3 of 16 (19%) patients with gut tumors. Only 1 of 13 patients with midgut tumors had increased plasma-neurotensinlike immunoreactivity, despite the fact that most of the normal neurotensin-containing cells are located in the midgut. In 3 of 4 cases the concentration of plasma-neurotensinlike immunoreactivity decreased after streptozotocin or surgical treatment. In 1 patient, increasing levels of plasma-neurotensinlike immunoreactivity were found several months before the onset of clinical symptoms or signs of relapse after surgical treatment. Neurotensin was found in extracts of primary tumors and metastases. Plasma-neurotensinlike immunoreactivity in patients with "neurotensinomas" represents more than one molecular form, including neurotensin(1-13) and neurotensin(1-8). Neurotensin(1-8) in plasma may be a degradation product of neurotensin(1-13) released from the tumor tissue. We have not been able to relate any specific symptoms to elevated plasma-neurotensinlike immunoreactivity.
D007516:Adenoma, Islet Cell / Q000378:metabolism; D002276:Carcinoid Tumor / Q000378:metabolism; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009479:Neuropeptides; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism*; D013311:Streptozocin / Q000627:therapeutic use; D015043:Zollinger-Ellison Syndrome / Q000378:metabolism
D009419:Nerve Tissue Proteins; D009479:Neuropeptides; C031644:neurotensin-like immunoreactivity; D013311:Streptozocin