Recurrent distal cholangiocarcinoma and humoral hypercalcemia of malignancy: report of a rare case and literature review.

A 61-year-old Japanese woman presented with epigastric pain and jaundice. Imaging showed the presence of primary distal cholangiocarcinoma (DCC). A subtotal stomach-preserving pancreaticoduodenectomy was performed, followed by chemotherapy using S-1. However, second-line chemotherapy with gemcitabine and cis-diamminedichloroplatinum was required for the treatment of hepatic metastasis of the DCC 3 months following the surgery. Nine months after the surgery, the serum calcium and parathyroid hormone-related peptide concentrations were high, at 16.5 mg/dL and 28.7 pmol/L, respectively, which suggested the presence of humoral hypercalcemia of malignancy (HHM) secondary to the DCC. Moreover, marked leukocytosis, with a white blood cell count of 40,400/μL, was also present. The patient died 11 months after the diagnosis of DCC. Because hypercalcemia of malignancy is associated with a poor prognosis, and HHM and leukocytosis caused by DCC are very rare, we have presented the present case in detail and provide a review of the existing literature.