Impact Of Extent Of Surgery On The Prognosis For CN1a Unilateral Differentiated Thyroid Cancer

Objectivedifferentiated thyroid carcinoma(DTC)has some characteristics like high incidence rate,slow progress and good prognosis,which makes higher demands for living quality after surgery.Preoperative evaluation plays an important role in the surgery options.The extent of surgery of unilateral DTC with positive clinical central lymph node(cN1a)has been in controversy.In recent years,recommendations by thyroid carcinoma guidelines and risk stratification for the prediction of persistent or recurrent disease have adapted to clinic.The trade-off between surgical options and survival benefits has also been a hot topic.The aim of this study was to discuss the association between the extent of surgery and the clinical outcome of patients with cN1a DTC.MethodsPatients with unilateral cNla DTC in Shandong Provincial Hospital from 2012 to 2017 were retrospectively reviewed according to the inclusion criteria and exclusion criteria.Group A patients had total thyroidectomy with central lymph node dissection and group B had thyroid lobectomy with central lymph node dissection.Basic information and perioperative clinical data were collected,including gender,age,ultrasonic results of thyroid and cervical lymph nodes,intraoperative and postoperative pathological data,postoperative hematoma,wound infection,recurrent laryngeal nerve(RLN)palsy and hypocalcemia.Follow-up of patients involved the information of nerve palsy,hypocalcemia and recurrence.The data was analyzed by R 3.6.1 software to compare the effects of two methods of surgery on the prognosis and complications.ResultsAmong 3140 thyroid carcinoma patients,180 DTC with cN1a were included.Group A had 99 patients and group B had 81 patients.The median follow-up time was 48 months.Patients with lymphatic metastasis was 85(47.2%),multifocality 27(15.0%),extrathyroidal extension 27(15.0%).locoregional recurrence occurred in 2 cases in each group.There was no statistical difference in the two groups.The association between the type of surgery and locoregional recurrence remained nonsignificant after adjusting for potential confounders such as lymph node metastasis,extrathyroidal extension and RAI.However,the rates of temporary RLN palsies and permanent hypocalcemia were higher than expected in group A and higher than rates in group B with statistical significance.ConclusionFor DTC patients with cN1a,no advantages of total thyroidectomy were found with respect to recurrence rate.But the risk of total thyroidectomy over lobectomy was increased with respect to temporary RLN palsy and permanent hypocalcemia.