Abstract:Background: The purpose of this study was to determine the relationship between calcifi cations in the thyroid gland and malignant thyroid lesions. Methods: From June 2005 -May 2010, 169 patients, who had been operated on for thyroidectomy, were evaluated. The demographic fi ndings were analyzed with regard to ultrasonographic and histopathologic calcifi cations. The relationship between calcifi cations and malignant and benign thyroid lesions was statistically determined by SPSS 10.01 version of Z-test and Chi-square test. Results: Microcalcifi cations were found in 54 patients (31.95 %). Macrocalcifi cation was found in one patient (0.59 %). Malignancy was determined in 29 patients (17.16 %). The rate of malignancy in patients with calcifi cations was 17/55 (30.9 1%). The diagnosis was nodular colloidal goiter in 38 patients (38/55, 69.09 %) with calcifi cations. The rate of calcifi cation in malignant patients was 17/29 (58.62 %). The rate of malignancy in patients without calcifi cation was 12/114 (10.52 %). The difference between the rate of malignancy in patients with calcifi cation and the rate of malignancy in patients without calcifi cation was statistically signifi cant (Z-test, p < 0.001). Conclusion: Microcalcifi cations of the thyroid gland could predict malignant thyroid disease. They should be strictly evaluated by all thyroid cancer diagnostic modalities and surgical treatment should also be considered (Tab. 4, Ref. 29 The high prevalence of thyroid nodules and the risk of malignancy are serious problems in thyroid surgery. Approximately 3 -7 % of adult populations have palpable thyroid nodules; however, only 5 % of clinically detected nodules are malignant (1, 2, 3).Although the incidence of well-differentiated thyroid carcinoma has been reported in up to 36 % in autopsy series, it is proven histopathologically in about 10 % of patients who undergo surgery. Fine-needle aspiration cytology samples are insuffi cient for the diagnosis, and up to 28 % of the patients studied showed nondiagnostic and false positive results (4, 5).Patients with calcifi cations in the thyroid gland are still a clinical dilemma. When a calcifi cation is detected in the gland, a question arises as to whether this is a predictive sign for malignancy or not. Microcalcifi cations were reported in 60 % of malignant nodules (6). The specifi city of microcalcifi cation for malignancy increases in young patients who exhibit single nodules with a snow-storm pattern on ultrasound (7). On the other hand, though the specifi city of microcalcifi cations increase to 95 % for papillary cancer, the sensitivity is low; 29-59 % of papillary carcinomas are seen with microcalcifi cations (8).Calcifi cations may be easily recognized by thyroid ultrasonography (US) or histopathological examination. Although high frequency ultrasound transducers increased the sensitivity of ultrasonography, they are not suffi cient to determine the malignancy. Calcifi cations can be in macro-or microcalcifi cation form. Macrocalcifi cations are great...