CALCA and thyroid nodule: Given the peculiar clinical picture, characterized by an ambiguous finding of hypercalcitoninaemia in the context of a thyroid nodule without a certain diagnosis of benignity and the greater sensitivity and specificity of the measurement of serum calcitonin in the suspicion of a C-cell pathology [23], we decided to perform a calcium stimulation test: 10% calcium gluconate at a dosage of 25 mg/Kg b.w. was administered intravenously at 10 mL/min with serial blood sampling before and, subsequently, after 1, 2, 3, 5, 10, and 15 min following the infusion.