Comparative Study Of Microwave Ablation And Lobectomy In The Treatment Of Benign Thyroid Nodules Greater Than 4cm

Objectives:To evaluate the safety and effectiveness of ultrasound-guided microwave ablation(MWA)versus lobectomy for the treatment of benign thyroid nodules>4cm.Methods:This study collected a total of 118 patients with benign thyroid nodules greater than 4 cm in diameter treated by ultrasound-guided microwave ablation and unilateral thyroid lobectomy at China-Japan Union Hospital of Jilin University from December 2018 to December2019.We retrospectively analyzed the data of 60 patients who underwent MWA and 58 patients who underwent lobectomy to treat benign thyroid nodules>4cm.All nodules were single or fused with each other on one side,the nodules in MWA group were confirmed as benign nodules by core needle biopsy(CNB)before MWA.The nodules in the lobectomy group were confirmed to be benign by rapid pathology during the operation.All patients were followed up for 12 months to observe the changes in the maximum diameter and volume of the nodule,the volume reduction ratio(VRR)and average ablation energy were calculated.The operation time,incision length,hospitalization time,complications,thyroid function,symptoms and cosmetic improvement were analyzed and compared between the two groups.Results:During the 12-month follow-up,the average maximum diameter of the nodules in the patients in the MWA group decreased from5.04±1.01cm(4.01cm-8.40cm)before ablation to 2.47±0.65cm(1.03cm-4.27cm),and the average volume It was reduced from33.74±22.29 cm~3(9.07 cm~3-128.60 cm~3)before MWA to 3.86±3.87 cm~3(0.30 cm~3-19.94 cm~3),which was significantly smaller than that before operation(P<0.001);At 1 month,3-month,6-month,and 12-month after MWA,the VRR were 51%±16%,70%±12%,81%±9%,89%±5%.The inactivation of nodules is equivalent to the surgical effect.The average ablation energy of unit volume of nodules was 0.92±0.66 k J/cm~3.All 58 patients in the operation group successfully underwent unilateral thyroid lobectomy.In terms of operation time,hospitalization time and incision length,the MWA group was significantly better than the operation group(P<0.001);in terms of changes in thyroid function,the MWA group There was no significant change in the patients’thyroid function after MWA.In the operation group,11 cases had subclinical hypothyroidism,and 6 cases were diagnosed as hypothyroidism.They were relieved by taking levothyroxine sodium,which was significantly different from the ablation group(P<0.001).In addition,the MWA group had fewer complications and a lower incidence of postoperative pain than the surgery group.In the evaluation of the cosmetic results,the MWA group had a higher degree of cosmetic satisfaction(P<0.001).During the 12-month follow-up,no nodules recurred in both groups.Conclusions:(1)Ultrasound-guided microwave ablation is a safe and effective method for the treatment of benign thyroid nodules with a diameter>4cm;(2)Compared with thyroid lobectomy,ultrasound-guided microwave ablation has the advantages of faster recovery,fewer complications,better protection of thyroid function,and better cosmetic effects.