Abstract:Objective:To investigate the calcification of thyroid nodule detected on ultrasound and the relation with benign and malignant disease. Methods:Data of 107 cases of malignant and 703 cases of benign thyroid nodules examined by high-resolution colored ultrasonography preoperatively and pathological diagnosis by paraffin embedded slides postoperatively were collected from our hospital over a period of 3 years. The percentages of calcification and fine stippled psammomatous(FSP) calcification in benign and malignant nodular disease, in different sexes and different age groups were retrospectively reviewed. Results:The incidences of calcification and FSP calcification were significantly higher in malignant group(63.55%, 29.02%, respectively) than in benign group（P＜0.001）. There was no significant difference between male and female groups(24.3%, 1.99%, respectively)（P＞0.05）. Calcification rate showed no significant difference between different age groups(＜45 and ≥45）（P＞0.05）; however, there was a significant difference of the FSP calcification rate between different age groups (P＜0.001）. The sensitivity of malignancy diagnosis was significantly higher in the group of patients younger than 45 years of age with FSP calcification of thyroid nodule. Conclusions:When calcification is noted on ultrasonography, it should raise the clinical index of suspicion for malignancy. FSP Calcification is a very highly specific in prediction of thyroid malignancy.