What is the optimal tissue sampling at endoscopy for diagnosis of BO?
Barrett’s Oesophagus can be suspected endoscopically but it is the histological confirmation of specialised intestinal metaplasia (SIM) that supports its diagnosis and confers an increased risk of development of neoplasia. SIM can be patchy within oesophageal columnar-lined mucosa, and may therefore not be consistently sampled with endoscopic biopsies, underlining the importance of a systematic approach to maximize the yield of biopsies.
The current standard for tissue sampling
Advancements in chromoendoscopy, endoscope digital enhancements and enhanced-magnification have not been shown to be significantly superior to the currently accepted practice of random four-quadrant biopsies at 2cm intervals.  The diagnostic yield for SIM may be higher with increasing number of biopsies obtained. If there is concurrent erosive oesophagitis, acid suppressive therapy should be optimised before repeating the endoscopy with further biopsies in two to three months.
Prior to biopsy acquisition, adequate time must be devoted to careful endoscopic inspection using high-resolution white light endoscopy (HR-WLE) for any focal abnormality such as ulcerated or nodular lesions which should be specifically biopsied and labelled prior to random biopsies from the rest of the mucosa as minor biopsy-related bleeding is common and may impair endoscopic views. Spraying dilute adrenaline may improve visibility and efficiency during random biopsies of long-segment Barrett’s but this is not routinely practised.
To maximise the size of tissue fragment biopsied, the open jaw of the biopsy forceps at the tip of the endoscope should be directed perpendicular to the targeted mucosal surface using endoscope angulation and torque, before applying endoscope suctioning and closing the forceps jaw. Jumbo biopsy forceps (jaw outer diameter 2.8mm) are often utilised but this has not been shown to be superior to large capacity (jaw outer diameter 2.4mm) and standard capacity (jaw outer diameter 2.2mm) forceps in obtaining adequate biopsy samples.
Technological advancements in chromoendoscopy (methylene-blue, indigo carmine, and acetic acid), digital enhancements (Narrow-Band Imaging, i-SCAN, Fujinon Intelligent Chromo Endoscopy) and enhanced-magnification can complement rather than replace the current practice described above for diagnosing SIM. Whilst promising, these techniques may not be superior to existing practice and may be impractical, time-consuming and costly. Ongoing studies will define their role in routine clinical practice.
Office-based unsedated transnasal endoscopy using paediatric biopsy forceps (jaw outer diameter 1.8mm) is well-tolerated and may emerge as a cost-effective screening option for the diagnosis of Barrett’s Oesophagus.
Evidence summary and recommendations
|SIM can be patchy within oesophageal columnar-lined mucosa and may not be consistently sampled with endoscopic biopsies.||IV|||
|Advancements in chromoendoscopy, endoscope digital enhancements and enhanced-magnification have not been shown to be significantly superior to the currently accepted practice of random four-quadrant biopsies at 2cm intervals.||I, II, IV||, , |
|The diagnostic yield for SIM may be higher with increasing number of biopsies obtained.||IV|||
|Jumbo biopsy forceps has not been shown to be superior to large capacity and standard capacity forceps in obtaining adequate biopsy samples||II|||
|Office-based unsedated transnasal endoscopy using paediatric biopsy forceps is well-tolerated and may emerge as a cost-effective strategy.||II||, , |
|The current practice of random four-quadrant biopsies at 2cm intervals remains the mainstay for tissue sampling until stronger evidence emerges for various advancements in endoscope technology and chromoendoscopy.||B|
Focal abnormalities such as ulcerated or nodular lesions can be specifically targeted with biopsies and labelled prior to random biopsies from the rest of the mucosa as minor biopsy-related bleeding is common and may impair endoscopic views.
Technological advancements in chromoendoscopy, digital enhancements and enhanced-magnification can currently complement rather than replace random four-quadrant biopsies at 2cm intervals. Biopsies obtained every 2cm to be placed into separate jars which are labelled according to the distance from the incisors, while biopsies from the gastro-oesophageal junction and cardia can also be specifically labelled as such.
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