PTHrP, calcitonin and calcitriol in a case of severe, protracted and refractory hypercalcemia due to a pancreatic neuroendocrine tumor.
A patient with a primary neuroendocrine tumor of the pancreas, presented with severe hypercalcemia. This hypercalcemia of malignancy (HCM) failed to respond to intensive bisphosphonate treatment and needed continuous enhanced diuresis. Only after successful antitumor therapy did the hypercalcemia subside. Hypercalcemia was associated with increased concentrations of plasma PTHrP, calcitonin and 1,25-(OH)(2)D(3). Bone mineral density was markedly increased. We demonstrated the presence of both PTHrP and calcitonin in the tumor at the mRNA and protein level, using RT-PCR, immunohistochemistry and Western blotting. The high levels of plasma PTHrP and the demonstrated predominant renal mechanism in this case of HCM are suspected to be the cause for its refractoriness to bone resorption inhibitors. Our findings furthermore suggest that the tumoral production of calcitonin and PTHrP might have contributed to the increased bone mineral storage of calcium and thus probably attenuated the development of frank hypercalcemia.
Van den Eynden
Gert G
GG
Translational Cancer Research Group Antwerp (Department of Pathology University of Antwerp/University Hospital Antwerp, 2650 Edegem, Belgium.
Neyret
Aymeric
A
Fumey
Glawdys
G
Rizk-Rabin
Marthe
M
Vermeulen
Peter B
PB
Bouizar
Zhor
Z
Body
Jean-Jacques
JJ
Dirix
Luc Y
LY
D001483:Base Sequence; D015519:Bone Density; D002116:Calcitonin / Q000097:blood / Q000235:genetics; D002117:Calcitriol / Q000097:blood; D004231:Diuresis; D006801:Humans; D006934:Hypercalcemia / Q000097:blood* / Q000209:etiology* / Q000235:genetics / Q000628:therapy; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000097:blood* / Q000150:complications* / Q000235:genetics; D010190:Pancreatic Neoplasms / Q000097:blood* / Q000150:complications* / Q000235:genetics; D044162:Parathyroid Hormone-Related Protein / Q000097:blood / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D044168:Receptor, Parathyroid Hormone, Type 1 / Q000235:genetics
D044162:Parathyroid Hormone-Related Protein; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D044168:Receptor, Parathyroid Hormone, Type 1; D002116:Calcitonin; D002117:Calcitriol