The Efficacy and Safety of Prophylactic Central Lymph Node Dissection in Papillary Thyroid Carcinoma

Study Overview
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Brief Summary
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The aim of this study is to investigate the efficacy and safety of prophylactic central lymph node dissection in papillary thyroid carcinoma.

Detailed Description
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The aim of this study is to investigate the efficacy and safety of prophylactic central lymph node dissection in papillary thyroid carcinoma. Primary outcome is the surgical completeness, recurrence rate, and successful ablation rate. Secondary outcomes are the incidence of postoperative complications and PTC stage. The enrolled patients were randomly assigned to control group and intervention group (1:1 allocation).

Official Title
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The Efficacy and Safety of Prophylactic Central Lymph Node Dissection in Papillary Thyroid Carcinoma

Conditions
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Thyroid Cancer, Papillary

Intervention / Treatment
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* Procedure: prophylactic central lymph node dissection


Participation Criteria
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Eligibility Criteria
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Inclusion criteria were as follows: patients aged 20 to 70 years old patients diagnosed with PTC or suspicious for PTC on fine needle aspiration or core needle biopsy patients with no evidence of LNM before and during surgery(cN0) patients with no evidence of distant metastasis(cM0). Exclusion criteria were as follows: patients suspected of advanced PTC(clinically T3 or T4) such as invasion of peripheral organs on preoperative examination patients who have previous history of cervical radiation therapy or surgery. pregnant women uncontrolled diabetes, hypertension, or chronic renal failure aspirin or anticoagulant medication within 7 days other clinical trial participation within 30 days radiation exposure to the head and neck previous operation to the neck advanced thyroid cancer including adjacent organ invasion

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: No prophylactic central dissection<br>Patients underwent total thyroidectomy for papillary thyroid carcinoma, without prophylactic central lymph node dissection | |
| Active Comparator: Prophylactic central dissection<br>Patients underwent total thyroidectomy for papillary thyroid carcinoma, with prophylactic central lymph node dissection | Procedure: prophylactic central lymph node dissection<br>* dissection of level VI compartment by AAHNS (American association of head and neck surgeons) classification<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of participants with successful surgical completeness | In the case of patients undergoing RAI ablation, surgical completeness was defined as cases with a negative ultrasonographic finding with postoperative 1st stimulated Tg <1 ng/mL. In patients who did not undergo RAI treatment, the case with a negative finding at the 1st postoperative ultrasound with postoperative 1st unstimulated Tg <0.2ng/mL was defined as surgical completeness. | Participants will be followed from the operation to 5 year (maximum) | 
| Recurrence rate of thyroid cancer | Recurrence was defined according to the definition of response to therapy in the 2015 American Thyroid Association(ATA) guidelines. | Participants will be followed from the operation to 5 year (maximum) | 
| Number of participants with successful ablation | Successful ablation was defined as a patient whose stimulated Tg level was measured as <1 ng/mL at last ablation. | Participants will be followed from the operation to 5 year (maximum) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative complication occurrence rate | At outpatient clinic (6months posteoperatively), video laryngoscopic exam and serum parathyroid hormone with serum calcium will be measured. Type and number of complications will be recorded | Participants will be followed from the operation to 5 year (maximum) | 
| impact of prophylactic central lymph node dissection on staging of papillary thyroid cancer(PTC) | Postoperative complications was divided into transient complication (< 6 months) and permanent complication (≥ 6 months) according to the duration. Hypoparathyroidism was diagnosed when patients were given oral calcium supplements to relieve symptoms of hypocalcemia or when serum parathyroid hormone (PTH) levels were lower than baseline values;1) PTH <10 pg/mL on days 1 and 14 after surgery; and 2) PTH <15 pg/mL at least 3 months after surgery. All patients underwent a laryngeal ultrasound or laryngoscope after surgery to check for RLN injury. RLN injury was diagnosed when the vocal cord movement was hypomobile or fixed on evaluation. In addition, present study evaluated symptoms related to voice changes, such as hoarseness, thickened voice, difficulty in making high pitch sound, easy voice fatigue, aspiration, or dyspnea in an outpatient clinic. | TNM stage of each case was confirmed after final pathologic reports. At our facility, final pathologic reports would be turned out at an average of 2 weeks after surgery |