Association between computed tomography-detected calcification and thyroid carcinoma

Abstract

This study aimed to investigate the diagnostic value of calcification detected by computed tomography (CT) for the differentiation of benign and malignant thyroid nodules. This is a retrospective study of 930 consecutive patients (709 women, 221 men; mean age 51 years) with pathologically proven thyroid nodules. The characteristics of calcification on CT images were correlated with the pathological results. A total of 168 patients were pathologically diagnosed with thyroid carcinomas and 762 patients with benign thyroid nodules. Calcification was found in 231 cases (24.84%). The incidence of calcification was significantly higher in patients with thyroid carcinoma (52.38%) than in those with benign nodules (18.77%; P < 0.001). Detection of calcification in diagnosing thyroid carcinoma had a sensitivity of 52.38% (88/168) and specificity of 81.23% (619/762). No significant difference was noticed in the incidence of microcalcification (≤ 2 mm) between malignant and benign nodules (P = 0.305). Calcification is more frequently found in thyroid carcinomas than benign nodules. CT detected-calcification may suggest malignant disease. Further confirmation of the suspected malignancy with fine-needle aspiration or surgery is still needed.

Is Ultrasonography More Sensitive Than Computed Tomography for Identifying Calcifications in Thyroid Nodules?

“…The agreement between US and pathologic analysis was significantly higher than that between CT and pathologic analysis. The inferiority of CT for identification of calcifications may be due to its inability of identifying calcifications that are less than 1 mm in size 4. Kim13 also found that CT was inferior to US for detecting microcalcifications.…”

“…However, these calcifications found on preoperative US are often missed or invisible on CT of the neck in the same patient 5,13. The incidence of calcifications detected by US is reported to be approximately 34.3% to 53.5%,7,8,10,13,19 which is higher than that for CT, which is reported to be approximately 24.8% to 35.2% 4,5,13…”

“…Calcifications are common findings in thyroid imaging. They may be present in various patterns and occur in both benign and malignant thyroid lesions 4–13. Microcalcifications, which are histopathologically known as psammoma bodies, are highly correlated with malignant tumors 5,7–9.…”

CT-detected solitary thyroid calcification: an important imaging feature for papillary carcinoma

“…Calcification is a common phenomenon in both benign and malignant thyroid nodules, 15 , 16 and the incidence of calcification in malignant nodules is higher. 17 , 18 Many studies have assessed various calcifications for their diagnostic value in benign and malignant nodules. 5 , 10 , 15 – 18 Solitary calcified thyroid nodules are examples of single coarse calcifications without visualization of the surrounding low-density focus whose density is lower than the normal thyroid gland tissue.…”

“… 17 , 18 Many studies have assessed various calcifications for their diagnostic value in benign and malignant nodules. 5 , 10 , 15 – 18 Solitary calcified thyroid nodules are examples of single coarse calcifications without visualization of the surrounding low-density focus whose density is lower than the normal thyroid gland tissue. 17 Kwak et al 19 reported that cases that show solitary calcified nodules without soft tissue involvement can be diagnosed as thyroid papillary carcinoma on ultrasound, and Ma and Li 20 also showed that malignant pathology was present in 40% of five cases on ultrasound.…”