Combined Hepatocholangiocarcinoma Associated with Humoral Hypercalcemia of Malignancy and Chronic Inflammatory Demyelinating Polyneuropathy.

Paraneoplastic syndromes are often a diagnostic challenge to doctors and may have a heterogeneous presentation, including humoral hypercalcemia of malignancy (HHM), most commonly caused by squamous cell cancer and renal, ovarian, endometrial, and breast cancer. Chronic inflammatory demyelinating polyneuropathy (CIDP) has been described in patients affected by several types of cancer, especially hematologic malignancies, and a possible paraneoplastic pathogenesis of this neurological disease has been suggested. This report describes a 56-year-old man with a history of CIDP diagnosed 3 months earlier and persistently elevated aminotransferases for 18 months who was admitted to our internal medicine unit with abdominal pain, fatigue, and severe hypercalcemia with low serum intact parathyroid hormone. Parathyroid hormone-related protein (PTH-rP) was markedly high. Liver imaging showed a large hepatic mass in the right lobe, and percutaneous ultrasound-guided biopsy revealed histopathological findings consistent with a combined hepatocholangiocarcinoma (CHCC). We supposed that both HHM and CIDP could represent a paraneoplastic manifestation of CHCC.