Calcitonin immunoreactivity and hypercalcitoninemia in two patients with sporadic, nonfamilial, gastroenteropancreatic neuroendocrine tumors.
BACKGROUND
Hypercalcitoninemia in gastroenteropancreatic tumors associated with calcitonin immunoreactivity is rare.


METHODS
We report here two patients in whom pancreatic neuroendocrine tumors both contained and secreted immunoreactive calcitonin. Both patients experienced elevated basal calcitonin immunoreactivity.


RESULTS
The peak responses of immunoreactive calcitonin occurred 5 minutes after pentagastrin administration in these two patients and were 30% and 180% above basal concentrations corresponding to peak increments of 0.39 and 8.78 ng/ml, respectively. The immunoreactive calcitonin response to pentagastrin in these two patients was not significantly different from that seen among five patients with medullary carcinoma of the thyroid gland.


CONCLUSIONS
It does not appear that immunoreactive calcitonin responses to pentagastrin stimulation will discriminate between patients with medullary carcinoma of the thyroid gland and those with nonfamilial, gastroenteropancreatic neuroendocrine tumors that express calcitonin immunoreactivity. In patients with secretory diarrhea and/or flushing, an elevated level of immunoreactive calcitonin, in the absence of a thyroid mass in the neck, may herald the presence of a gastroenteropancreatic neuroendocrine tumor.
McLeod
M K
MK
Department of Surgery, University of Michigan Medical School, Ann Arbor.
Vinik
A I
AI
D007516:Adenoma, Islet Cell / Q000097:blood* / Q000601:surgery; D000368:Aged; D002116:Calcitonin / Q000097:blood*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000097:blood / Q000556:secondary; D008875:Middle Aged; D009377:Multiple Endocrine Neoplasia / Q000097:blood* / Q000601:surgery; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000601:surgery; D010191:Pancreatic Polypeptide / Q000097:blood; D010418:Pentagastrin; D013274:Stomach Neoplasms / Q000097:blood* / Q000601:surgery; D013964:Thyroid Neoplasms / Q000097:blood; D014660:Vasoactive Intestinal Peptide / Q000097:blood
D014660:Vasoactive Intestinal Peptide; D010191:Pancreatic Polypeptide; D002116:Calcitonin; D010418:Pentagastrin