BACKGROUNDThe primary treatment for locoregional recurrent/persistent differentiated thyroid cancer (DTC) is repeated lymph node dissection; however, there are limited reports on the safety and long-term efficacy of multiple operations.METHODSPatients who underwent a cervical lymph node dissection between 1998 and 2022 were included in this study. Demographics, initial thyroid surgery, subsequent lymph node dissections, follow up information, and response to therapy were acquired.RESULTSAfter one, two, three and four re-operations, 112/314 (35.7 %), 16/79 (20.3 %), 3/25 (12 %), and 0/3 (0 %) patients (p < 0.001) had an excellent response, respectively, resulting in a cumulative rate of 41.7 % (131/314). The risk for permanent hypoparathyroidism (2.9 %) or recurrent laryngeal nerve injury (2.2 %) was 5.1 % (14/272). This was higher in patients undergoing re-operative central neck dissection (CNDx) (8.7 %, 10/114) versus those who did not undergo a previous CNDx (2.5 %, 4/158, p < 0.02).CONCLUSIONSSurgery remains the primary treatment for recurrent/persistent DTC, however, the likelihood of an excellent response decreases with additional operations. The risk of permanent complications is low but is more likely to occur during redo CNDx.