Intermediate High-frequency Ultrasound in the Differential Diagnosis of Cystic-solid Thyroid Nodules: A Retrospective Study

Background: Thyroid nodules are a common clinical problem that has a steady increase in incidence rate over the last several decades.Cystic thyroid solid nodules usually have an indolent manifestation in ultrasonography.The ultrasound with an intermediate high-frequency range of 8-15 MHz, high resolution and appropriate penetration, has been widely used for superficial tissues examination.The aim of this study is to investigate the value of intermediate high-frequency ultrasound in the differential analysis of cysticsolid papillary thyroid cancer (PTC) and cystic nodular goiter changes.Method: Retrospective analysis of the ultrasonographic features from 41 cases of cystic solid thyroid cancer (16 males and 25 females) and 95 cases of nodular thyroid cystic changes (20 males and 75 females) was carried out.Results: In cystic-solid PTC, the solid parts were mostly distributed eccentrically and had some microcalcifications, the cystic interface was usually irregular.In cystic-solid nodular goiter, the solid parts were distributed symmetrically without microcalcification, and the cystic interface was mainly regulated.Above all, the differences in the morphology of the solid parts, microcalcification, and cystic interface between cystic papillary thyroid carcinoma and cystic nodular goiter were statistically significant (P<0.05).Furthermore, multi-factorial analysis revealed that age, microcalcification in the solid section, eccentric configuration of the solid section, and irregularity of the cyst-solid interface were independent risk factors for cystic PTC.Conclusion: Cystic-solid PTC under intermediate high-frequency ultrasonography exhibits some definitive features, and a preoperative ultrasonography is helpful for the diagnosis of cystic-solid thyroid lesions.Key wordsIntermediate high-