[Calcitonin determination for early diagnosis of medullary thyroid cancer].

Calcitonin is considered to be a sensitive marker for medullary thyroid cancer (MTC) therefore early detection and surgical treatment may help to improve the clinical prognosis of MTC. Routine calcitonin measurement has therefore been recommended in the diagnostic evaluation of patients with nodular thyroid disease. In the case of elevated serum calcitonin (>20 pg/ml) stimulation testing is recommended to improve the predictive power for MTC particularly in patients with small nodules. Serum calcitonin measurement cannot reliably discriminate between micro-MTC (<10 mm) and C cell hyperplasia. In patients with stimulated calcitonin levels exceeding 100 pg/ml thyroidectomy is recommended because of a high inherent risk of MTC. Highly elevated basal and stimulated serum calcitonin levels are strongly suggestive of MTC with practical implications for surgical management.