Traditional 2-dimensional ultrasound assessment is highly sensitive in detecting the extrathyroidal extension of thyroid cancer in the anterior capsule, according to the results of a new study published in the International Journal of General Medicine.

However, the detection of extensive extrathyroidal extension and extrathyroidal extension in the posterior capsule is more effective when transcapsular blood flow is used.

In the present study, a team of researchers from China conducted a retrospective study to compare the diagnostic efficacies of 2-dimensional ultrasound and transcapsular blood flow in mild, severe, anterior, and posterior extrathyroidal extension.

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They assessed the efficacies of the 2 methods using 208 thyroid cancer nodules. Of these, 199 were from cases of papillary carcinoma, 5 were from cases of medullary thyroid carcinoma (MTC), and 4 were from cases of follicular carcinoma.

Extrathyroidal extension is an important factor that affects the prognosis of thyroid cancer. While mild extrathyroidal extension, which usually invades the infrahyoid muscles, does not seem to affect prognosis, moderate to severe extrathyroidal extension does.

It is therefore of great importance to accurately evaluate extrathyroidal extension of thyroid cancer preoperatively to reduce postoperative recurrence and ensure that the right treatment plan is adopted, which will prolong survival and improve quality of life in affected patients.

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Extrathyroidal extension is routinely detected using 2-dimensional ultrasound. However, the sensitivity and specificity of this approach are not perfect and, therefore, do not improve prognosis.

The results showed that the size of the tumor and the sex of the patient were correlated with the occurrence of extrathyroidal extension.

“The general method is more accurate for the overall identification of [extrathyroidal extension] but is not specific enough for severe [extrathyroidal extension], while the transvascular method is the opposite,” the researchers concluded. 


Li Z, Chen S, Li J. The significance of transcapsular blood flow for assessing moderate to severe extrathyroidal extension: results of a two-center study. Int J Gen Med. 2022;15:1341-1347. doi:10.2147/IJGM.S349299