Hypercalcemia in metastatic pancreatic neuroendocrine tumor: a case report of ectopic 1,25 hydroxyvitamin D production by tumor cells and tumor-associated macrophages.

ABSTRACT:

Background

Hypercalcemia associated with neuroendocrine tumors (NETs) is typically attributed to increased circulating parathyroid hormone-related protein (PTHrP). However, several cases have now been reported in which hypercalcemia is linked to increased serum 1,25-dihydroxyvitamin D [1,25(OH)₂D]. Until now, the source of this ectopic 1,25(OH)₂D production had not been localized.

Case description

A 53-year-old Caucasian woman presented with hypercalcemia secondary to a metastatic grade 2 distal pancreatic NET, accompanied by a 4.6-fold increase in serum 1,25(OH)₂D. Her hypercalcemia responded to high dose prednisolone and normalized after staged resection of her primary tumor and hepatic metastases. 1,25(OH)₂D levels also normaliz

SUBMITTER: Lau SM 

PROVIDER: S-EPMC12780687 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature