Assessment of malignant potential of thyroid mass using computed tomography

BACKGROUND : Thyroid nodules are detected in 20-68% of patients. However, there is no data in the literature on the criteria for malignancy in CT studies. The introduction of CT into widespread practice has led to an increase in the detection of formations, including the thyroid gland, requiring additional examination. The use of additional imaging methods will improve the detection of malignant tumors of the thyroid gland. AIM : The purpose of this study was to address the gap in thyroid CT imaging and to evaluate whether contrast-enhanced multiphase multidetector CT is suitable for assessing the malignant potential of thyroid mass. MATERIALS AND METHODS : The study was conducted on the basis of the General Oncology Department No. 71 in Botkin Hospital from 2022 to 2023 A retrospective analysis of CT images included data from 146 electronic medical records of patients with differentiated carcinoma and follicular adenoma of the thyroid gland. A comparative evaluation was performed using contrast-enhanced CT (160 slices; Toshiba Aquilion Prime model) (Omnipaque 350 mg iodine/ml: 100 ml) with assessment in the native, arterial and venous phases. RESULTS : The study included 64 patients diagnosed with follicular adenoma of the thyroid gland and 82 patients with differentiated thyroid cancer. When assessing the relationship between thyroid carcinoma and tumor density in Hounsfield units, a positive correlation was revealed (Spearman correlation in the native phase r=0.48; arterial phase r=0.69; venous phase r=0.64; p<0.001). The sensitivity and specificity of assessing the density of thyroid nodules using CT data was analyzed. The most demonstrative results were demonstrated when analyzing CT scans in the arterial phase. At an arterial phase cut-off point of 121 Hounsfield units, the sensitivity was 75.6% and the specificity was 91.7%. Using a cutoff point of 113 Hounsfield units in the venous phase, the sensitivity was 62.2% and the specificity was 95.8%. In the native phase, a cut-off point of 49 Hounsfield units demonstrated a sensitivity of 68.9% and a specificity of 75%. CONCLUSION : Contrast-enhanced CT examination of the thyroid gland can become a promising method for the differential diagnosis of carcinomas and can be used in the presence of masses with unclear malignant potential.