Hypercalcemia due to PTHrp producing pancreas NET: A case report

Secretion of parathormone related peptide (PTHrp) is the most common cause of tumor-associated hypercalcemia. This occurs most often in squamous cell carcinomas in the ear nose and throat, bronchial and breast carcinomas. We report a rare case of a PTHrp-producing pancreatic neuroendocrine tumor (pNET) and provide a brief review of the literature.

A 68-year-old female patient with epigastric pain and weight loss was diagnosed with a 11 × 8 × 9 cm tumor in the pancreatic body with infiltration of the splenic vein and consecutive portal vein thrombosis without evidence of distant metastases. An endosonographic fine needle aspiration revealed a neuroendocrine tumor G2 (Ki-67 3 %). Laboratory analyses showed an asymptomatic hypercalcemia and elevated PTHrp. Distal splenopancreatectomy, left adrenalectomy, thrombectomy of the portal vein, cholecystectomy and partial resection of the left renal vein was performed. Histopathologic examination showed a PTHrp-producing NET of the pancreas G2, pT4 pN0 M0 L0 V2 Pn0 R0. Postoperatively serum levels of PTHrp and calcium dropped to normal values.

Up to date only 83 cases of PTHrp producing pNETs have been reported in the English literature. Frequently, as in the reported patient, locally advanced or already distantly metastasized tumors were present. In addition to initial drug control of hypercalcemia, surgical treatment in case of R0 resection offers long-term symptom control and should be performed, when possible.

In case of a pancreatic tumor and the simultaneous occurrence of hypercalcemia, the determination of PTHrp should be considered. Surgical resection remains the only curative therapy.