Objective: To summarize ultrasound features associated with medullary thyroid carcinoma (MTC) and investigate the predictive value of ultrasonography in preoperative diagnosis of MTC.
Methods: The sonographic and clinical data were studied in a series of nodules histologically proven as MTC collected from January 1993 to January 2013.
Results: A total of 86 patients (92 nodules proven as MTC) were enrolled in the study with an average age of (47±12) years.Among the MTCs, 21.7%(20/92) were excluded because of missing data and the remained 78.3%(72/92) had complete data with the average diameter of (2.1±1.3) cm.The common US findings for MTC were solid, hypoechogenicity, regular sharp, well-defined margin, AP/ TR<1 and calcification (mostly microcalcification). Calcification and vascularization were more common in MTC nodules(48.6% vs 5.6%, P=0.001). Nodules with enlargement of cervical lymph node tended to be undergone FNAB(76.0% vs 55.3%, P=0.084), and ill-defined margin was more common in MTC nodules with cervical lymph node metastasis(36.4% vs 12.8%, P=0.009).
Conclusion: Despite having a few US features closely linked to the malignant nodules such as solid, hypoechogenicity and with microcalcification, the MTC nodules also have specific US imaging characteristics as regular sharp, well-defined margin and AP/ TR<1.