Calcitonin-secreting pancreatic neuroendocrine tumor in a patient with elevated thyroid fine-needle aspirate calcitonin washout: A case report and review of the literature.

We report the unique case of a patient with previously proven non-functional PanNET and Graves' disease with thyroid nodules. The patient had elevated intranodular calcitonin, but no MTC or c-cell hyperplasia on thyroidectomy. They were found to have calcitonin secreting PanNET. This case presents a false-positive intranodular calcitonin.