Ultrasound Follow-up of Suspicious Neck Lymph Node Metastasis after Operation in Differentiated Thyroid Cancer

ZHAO Chunying

doi:10.3969/j.issn.1672-7185.2019.12.014

Abstract：Objective? To dynamically observe the ultrasonographic changes of suspicious lymph node metastasis after operation for differentiated thyroid cancer (DTC). Methods? A total of 53 patients with suspected lymph node metastasis after DTC in our hospital from 2010 to 2015 were retrospectively collected, and the sonographic features of suspected lymph node metastasis were recorded for the first time. The dynamic follow-up of ultrasound was continued to observe the sonographic changes of suspected lymph node metastasis. Results? The 315 patients with DTC, 16.83% had suspected lymph node metastasis after operation. The size of lymph nodes at the first detection was 5~11 mm in length, with an average of (7.2±1.7) mm, and 3~7 mm in short diameter, with an average of (4.2±1.1) mm. Internal sonography: punctate enhancement accounted for 50.94%; focal hyperechoicity accounted for 11.32%; cystic degeneration 7.55%. Lymphatic portal ultrasonography: disappearance accounted for 83.02%. During the follow-up, 4 cases were lost, 8 cases were withdrawn and 41 cases were followed up. The size of lymph nodes in 41 patients was basically unchanged (78.05%), increased (14.63%) and decreased (7.32%). Internal sonographic changes: punctate enhancement disappeared in 25.93%; focal hyperechoic disappeared in 33.33%; cystic degeneration disappeared in 25.00%. Ultrasonographic changes of lymphatic hilum: structural recovery accounted for 20.45% and maintenance disappearance accounted for 79.55%. Compared with the first detection of suspected lymph node metastasis, only one patient had enlarged lymph nodes with a diameter of more than 10 mm, and the other lymph nodes had significant changes in internal and lymphatic hilar ultrasonography. Conclusion? Most patients with suspected neck lymph node metastasis after DTC have no significant changes in ultrasound follow-up. For those with suspected lymph node diameter less than 10 mm, ultrasound follow-up can be continued, while those with longer diameter more than 10 mm should be vigilant against malignant transformation.