Aceto-whitening in the Assessment of Gastrointestinal Neoplasia

Acetic acid chromoendoscopy is an established standard technique used to detect dysplasia within the gastrointestinal tract. Acetic acid spray helps to identify neoplasia by highlighting the surface pattern, highlighting the vascular pattern and by a process known as the aceto-whitening reaction, where tissues take acetic acid and turn white for a brief period and then slowly revert back to a normal colour. The neoplastic surface and vascular pattern are all very well described, and have played a big role in the recognition of early cancer. The aceto-whitening reaction is well described but the differential in timing between neoplastic and non-neoplastic areas is not well understood. The investigators aim to establish the differential in the timing of the disappearance of the aceto-whitening reaction between healthy tissue, dysplastic tissue, intramucosal cancer and invasive cancer after acetic acid dye spray in the oesophagus and colon. By understanding this better, the investigators may be able to predict with greater accuracy whether a highlighted abnormal area is cancer or high grade dysplasia, or whether it is low grade dysplasia or inflammation, which has significant prognostic implications for the patient. The investigators hypothesize that the differential in the timing of the disappearance of the aceto-whitening reaction between normal and abnormal tissue could help in the detection of gastrointestinal neoplasia.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Patients with known Barrett's metaplasia under surveillance
* Patients with Barrett's metaplasia who had undergone endoscopic treatment for neoplasia previously and were under surveillance for metachronous neoplasia
* Patients suspected of neoplasia referred for endoscopic mucosal resection or other targeted endoscopic treatment of the lesion

Exclusion Criteria:

* Oesophagitis
* Contact bleeding
* Acute mucosal trauma