The Efficacy of N-acetylcysteine on Alleviating Symptom Caused by Lugol Chromoendoscopy

Study Overview
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Brief Summary
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Lugol chromoendoscopy is essential in detecting and characterizing squamous cell carcinoma of esophagus. Esophageal irritating symptom has been reported as an common adverse event, which could be alleviated by sodium thiosulfate solutions. However, sodium thiosulfate was not widely available. N-acetylcysteine has been previously used as a mucolytic reagent, we propose that it may also be used to alleviate irritating symptoms caused by Lugo's chromoendoscopy. A prospective, non-inferior, randomized double-blind clinical trial was designed to study the efficacy of N-acetylcysteine solutions in relieving esophageal discomfort .

Official Title
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The Efficacy of N-acetylcysteine on Alleviating Symptom Caused by Lugol Chromoendoscopy: a Prospective, Non-inferiority, Randomized Controlled Trial

Conditions
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Esophageal Squamous Cell Carcinoma

Intervention / Treatment
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* Drug: N-acetylcysteine solution
* Drug: sodium thiosulfate solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients at risk of esophageal squamous cell cancer including those over 50 years old, or over 45 years old with family history of esophageal squamous cell cancer; Patients with suspected esophageal lesions by screening endoscopy; Patients requiring surveillance after endoscopic resection or radiotherapy for esophageal squamous cell cancer one year later。 Exclusion Criteria: Patients allergic to iodine or with hyperthyroidism; Patients with advanced esophageal cancer, esophageal varices, esophageal ulcer or other conditions inadvisable for Lugol chromoendoscopy; Patients with severe gastroesophageal reflux disease or reflux symptoms which may interfered with the outcome measures of current study; Patients with postoperative esophageal stenosis affecting endoscopic observation; Patients with serious comorbidities that cannot tolerate un-sedated gastroscopy; Patients who could not cooperate with the observation including patients with mental disorders, severe neurosis or dysgnosia; Patients undergoing sedation or general anesthesia during endoscopy. Patients who do not agree to sign informed consent forms or follow the trial requirement.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: sodium thiosulfate solution arm<br>20ml of 5% sodium thiosulfate solution were prepared with 1g sodium thiosulfate crystal dissolved in normal saline in a 20 ml syringe | Drug: sodium thiosulfate solution<br>* use sodium thiosulfate solution to alleviate esophageal irritation caused by Lugol's chromoendoscopy<br>|
| Experimental: N-acetylcysteine solution arm<br>20ml of 3% N-acetylcysteine solution were prepared with one piece of N-acetylcysteine effervescent tablet （ net weight 0.6g ）dissolved in normal saline in a 20 ml syringe | Drug: N-acetylcysteine solution<br>* use N-acetylcysteine solution to alleviate esophageal irritation caused by Lugol's chromoendoscopy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Visual analogue scale change | Visual analogue scale change for esophageal irritation after Lugol chromoendoscopy | 30 minute after endoscopy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of patients with symptom | The percentage of patients with symptom after Lugol chromoendoscopy for certain time | 5 minute or 30 minute or 24 hour after endoscopy | 
| Neutralization rate | Neutralizing effect for residual iodine in esophagus and stomach | During endoscopy | 
| Heart rate variability | the percentage of heart rate change 5 min or 30 min compared to that Before endoscopy | 5 minute or 30 minute after endoscopy | 
| Severe discomfort rate | the percentage of patient with Visual analogue scale over 4 | 5 minute or 30 minute after endoscopy | 
| exam time | the time of endoscopy from the beginning of spraying diluted Lugol's solution to end of endoscopy minus time required for biopsy. | during endoscopy | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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lugol chromoendoscopy, adverse event