Can extent of high grade dysplasia in Barrett's oesophagus predict the presence of adenocarcinoma at oesophagectomy?

Background: Optimal management of Barrett's oesophagus complicated by high grade dysplasia is controversial. Recently, the extent of high grade dysplasia was described as a predictor of subsequent development of cancer in patients undergoing continued surveillance. However, there is no universal agreement on the definition of extent of high grade dysplasia. Aim: To determine if extent of high grade dysplasia in Barrett's oesophagus is a predictor of the presence of adenocarcinoma at the time of oesophagectomy. Methods: Forty two patients with Barrett's oesophagus and high grade dysplasia who underwent oesophagectomy between 1985 and 1999 were identified from a prospective database. All pathological specimens, including preoperative endoscopic biopsies and post-oesophagectomy sections, were reviewed in a blinded fashion by one expert gastrointestinal pathologist to determine the extent of high grade dysplasia. The extent of high grade dysplasia was defined using two different criteria, one from the Cleveland Clinic and one from the Mayo Clinic. Results: Twenty four of 42 patients (57%) had unsuspected cancer at the time of oesophagectomy. Using the Cleveland Clinic definition, 10 of 21 (48%) patients with focal high grade dysplasia had carcinoma compared with 14 of 21 patients (67%) with diffuse high grade dysplasia (p=0.35). Using the Mayo Clinic definition, adenocarcinoma was found in five of seven (72%) patients with focal high grade dysplasia compared with 19 of 35 (54%) with diffuse high grade dysplasia (p=0.68). Conclusions: The extent of high grade dysplasia, regardless of how it is defined, does not predict the presence of unsuspected adenocarcinoma at oesophagectomy. There is no evidence as yet that the extent of high grade dysplasia can be used as a basis for decision making in these patients.