Significance of Incidental Thyroid Lesions Detected on CT: Correlation Among CT, Sonography, and Pathology

Abstract

There is at least an 11.3% prevalence of malignant or potentially malignant lesions among incidental thyroid abnormalities detected on CT. Patients 35 years or younger who have incidental abnormalities have a significantly greater rate of malignancy. No CT feature reliably distinguishes benign from malignant lesions in the thyroid gland. CT underestimates the number of nodules relative to sonography, which suggests that sonography is a useful adjunctive test after the incidental detection of a thyroid abnormality on CT.

Incidental finding of papillary thyroid carcinoma on CT examination of mandibular lesion: Case report

“…Thyroid nodules appear with nodular or rim calcification on CT images and may likely be malignant (3). However, unlike US which has adequate spatial resolution such as microcalcification or margin detail, CT and MR images have no indicators to differentiate between benign and malignant tumors (6,7). Both benign and malignant tumors demonstrated intermediate signal intensity on T1WI and high signal intensity on T2WI, even if in our case showed high signal intensity in T1WI and STIR.…”

“…Both benign and malignant tumors demonstrated intermediate signal intensity on T1WI and high signal intensity on T2WI, even if in our case showed high signal intensity in T1WI and STIR. Additional investigations are required to determine malignancy such us US or FNA (7,(9)(10)(11).…”

“…On PTC case size and patient age are important for treatment consideration. Some study of PTC has grouping PTC based on size (2,7,10,11,13). PTC with <5 mm known as papillary thyroid microcarcinoma (PTMC), in elderly patients, progressivity of lesion was not evident during observation and immediate surgery was not needed (4,11,13).…”

“…As age is one of the considerations for PTC treatment, clinicians tend to focus on younger patients (7,10) as progression of the disease is more likely in younger patients compared to elderly patient (2,13). In addition, the ratio of malignant and benign was higher in younger patients, although age was not an independent predictor of PTMC (10,11,13).…”

“…Most of the malignant lesions in the thyroid are papillary thyroid carcinoma (PTC), followed by follicular, medullary, and anaplastic thyroid carcinoma (5). On CT or MRI, malignant nodules do not have specific imaging findings (6,7). PTC ≤1 cm is defined as papillary thyroid micro-carcinoma (PTMC), and it is the most prevalent type of papillary thyroid carcinoma.…”