Multifocal High-Grade Dysplasia (MFHGD) in Barrett's Esophagus Is Associated with Adenocarcinoma in Patients Undergoing Endoscopic Mucosal Resection (EMR) for Barrett's Esophagus

Abstract

Background: Risk of undetected adenocarcinoma in patients with high-grade dysplasia (HGD) is considered high. The extent of HGD has been suggested to be a risk factor for the development of cancer, but the predictive value of MFHGD as a marker for adenocarcinoma remains controversial. EMR can completely eradicate areas of Barrett's esophagus and it enables a complete pathologic evaluation of the Barrett's segment. Aim: To examine the extent of HGD in association with co-existing carcinoma in Barrett's esophagus in endoscopically resected specimens. Methods: Twenty-eight patients with Barrett's HGD or adenocarcinoma who underwent EMR between May 2005 and October 2006 were included in the analysis. All patients with HGD were planned for 2-staged complete eradication EMR. Two patients did not complete the eradication due to multifocal cancer in one and lymphovascular invasion (LVI) in another found at the first EMR. They subsequently underwent surgery, thus full pathology is available. One patient did not have subsequent follow up. All EMR specimens were retrieved and pinned on the corkboard, oriented, serially sectioned and submitted entirely for microscopic examination. Slides were independently reviewed by experienced gastrointestinal pathologists for presence and degree of dysplasia, carcinoma, and depth of invasion. MFHGD was defined as the presence of HGD at multiple levels of esophagus. Results: Fourteen pts were diagnosis with HGD and 14 with adenocarcinoma at surveillance biopsies prior to referral to the institution. Among the 14 pts with HGD, 4 pts had MFHGD. A total of 19 pts were confirmed with adenocarcinoma after EMR. Eight pts with adenocarcinoma (42%) had coexisting MFHGD. Three pts with a diagnosis of adenocarcinoma by biopsy (21%) did not have an evidence of cancer in EMR specimens and subsequent surveillance biopsy. Among the 14 pts who went to eradication EMR with a diagnosis of HGD, 7 (50%) had evidence of unsuspected adenocarcinoma in EMR specimens. All 4 pts with MFHGD (100%) had a focus of adenocarcinoma whereas 3 of 10 pts with focal HGD (30%) had adenocarcinoma. All adenocarcinoma in HGD group was diagnosed as intramucosal carcinoma. One patient in MFHGD group had intramucosal carcinoma with an evidence of LVI and underwent surgical resection. Conclusions: Adenocarcinoma is highly associated with co-existing MFHGD. MFHGD by surveillance biopsy suggested higher probability of undetected adenocarcinoma in this cohort of patients. Although larger studies are needed to confirm this finding, MFHGD may be used for risk stratification of patients with Barrett's esophagus, especially when choosing resection versus ablation therapy.