Somatostatin receptor expression in a parathyroid hormone-related peptide-secreting pancreatic neuroendocrine tumour causing severe hypercalcaemia.
BACKGROUND
Humoral hypercalcaemia is a common complication of malignancy with parathyroid hormone-related protein (PTHrP) as a major cause. Breast and lung cancer are relatively common sources of ectopic PTHrP secretion leading to increased osteoclastic bone resorption.


METHODS
We report the rare case of a 40-year-old man with severe hypercalcaemia due to a PTHrP-secreting poorly differentiated endocrine carcinoma of the pancreas. On immunohistochemistry, the tumour was positive for PTHrP and somatostatin receptors sst1, sst2, and sst3, whereas sst4 and sst5 were not detected. We demonstrate the transient improvement of hypercalcaemia after adding octreotide to the treatment mainstays in hypercalcaemia of malignancy (fluid repletion, administration of bisphosphonates, loop diuretics, and glucocorticoids).


CONCLUSIONS
To the best of our knowledge, this is the first report showing somatostatin receptor expression in a PTHrP-secreting pancreatic neuroendocrine tumour.
Müssig
Karsten
K
Department of Endocrinology, University Hospital of Internal Medicine, University of Tübingen, Germany. Karsten.Muessig@med.uni-tuebingen.de
Petersenn
Stephan
S
Wehrmann
Manfred
M
Horger
Marius
M
Vierling
Peter
P
Häring
Hans-Ulrich
HU
Gallwitz
Baptist
B
D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D018278:Carcinoma, Neuroendocrine / Q000150:complications / Q000188:drug therapy / Q000378:metabolism*; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology*; D008297:Male; D015282:Octreotide / Q000627:therapeutic use; D010190:Pancreatic Neoplasms / Q000150:complications / Q000188:drug therapy / Q000378:metabolism*; D010257:Paraneoplastic Syndromes / Q000209:etiology; D044162:Parathyroid Hormone-Related Protein / Q000378:metabolism*; D017481:Receptors, Somatostatin / Q000378:metabolism*; D014057:Tomography, X-Ray Computed
D018931:Antineoplastic Agents, Hormonal; D044162:Parathyroid Hormone-Related Protein; D017481:Receptors, Somatostatin; D015282:Octreotide