Mixed neuroendocrine–non–neuroendocrine neoplasm producing calcitonin: a diagnostic challenge

A 78-year-old woman with no significant past medical history was admitted to the Department of Internal Medicine and Endocrinology with a two-month history of progressive epigastric pain, watery diarrhea, fatigue, and unintended weight loss of 7 kg.Physical examination revealed cachexia, muscle atrophy, and massive hepatomegaly extending to the right iliac fossa.There were no clinical signs of infection.Abdominal ultrasound followed by contrast-enhanced computed tomography (CT) revealed a solid mass in the pancreatic head measuring 40 50 41 mm with 16-mm dilatation of the pancreatic duct and multiple liver metastases (Figure 1A).