Analysis of Withdrawal Time in Upper Gastrointestinal Endoscopy as Procedure Time: a Randomised, Parallel, Double-blinded, Multicenter, International Clinical Trial

Gastric cancer is the fifth cause of cancer-related mortality worldwide. Gastric carcinogenesis involves the progression from premalignant conditions such as atrophic gastritis and intestinal metaplasia to premalignant lesions like dysplasia, and ultimately carcinoma. Most diagnoses of gastric cancer are made at advanced stages, with a five-year relative survival rate of 36%. Therefore, early detection of premalignant conditions and lesions is crucial, as it allows for timely surveillance and treatment, which can improve patient survival.

Upper gastrointestinal endoscopy (UGE) is the first-line examination for diagnosing upper gastrointestinal tract pathology, particularly oncological conditions. The European Society of Gastrointestinal Endoscopy (ESGE) and the United European Gastroenterology (UEG) have established that UGE quality is a priority, identifying specific quality parameters, such as the duration of the procedure, which is the most extensively studied parameter.

According to ESGE recommendations, all UGE reports should include the procedure time (goal: ≥90% of reports), which should be seven minutes or longer for surveillance of intestinal metaplasia. This time threshold follows a study that established a causal relationship between longer procedures (≥ seven minutes) and a higher detection rate of premalignant gastric conditions and lesions. Subsequent observational studies have generally shown that setting a minimum procedure time increases the detection rate of lesions.

The definition of procedure time varies between studies, being described as the time from intubation to extubation, but also as the time for withdrawing the endoscope from the second portion of the duodenum (D2) to extubation, also known as withdrawal time.

The hypothesis under study is that a better definition of the most appropriate time for a diagnostic UGE could standardize reports, improve malignant lesion detection rates, and reduce the rate of undiagnosed cancers, without any additional risk to patients.

Existing studies have been retrospective or comparative between different temporal cohorts, with no prospective or randomised comparative studies, nor any studies comparing the two existing metrics. Therefore, the aim of this study is to evaluate the best metric for inspection time during a diagnostic and/or surveillance UGE, between total inspection time versus withdrawal time, for the identification of malignant lesions.