Ultrasound criteria of extra-nodal extension in papillary thyroid cancer metastases and its clinical significance

The purpose of the research was to identify ultrasound criteria of extranodal extension (ENE) in metastases of papillary thyroid cancer and to evaluate the clinical significance of ENE. Material and Methods. Ultrasound signs of ENE in 283 cervical lymph node metastases from papillary thyroid cancer were analyzed. Extranodal extension in 137 metastases was diagnosed by ultrasound and verified by histological examination. Micrometastases invisible on ultrasound were detected in 144 patients; metastases located inside the organ were detected in 147 patients; metastases located outside the organ were revealed in 136 patients; the size of 98 metastases was less than 1 cm; the size of 185 metastases was more than 1 cm; the age of 51 patients was under 55 years; 132 patients were older than 55 years. Diagnostic significance of ENE and its clinical significance were estimated according to X2Pirson criteria.