INTRODUCTION
Esophageal adenocarcinoma is one of the fastest growing cancers in incidence in the Western world (1). Despite advances in cancer care, esophageal cancer remains difficult to treat, and is associated with a poor survival rate of 14% at 10 years (2). Barrett’s esophagus is a significant risk factor for development of esophageal adenocarcinoma. Endoscopic surveillance has become the standard of care in following patients with Barrett’s esophagus and has allowed an increase in the diagnosis of earlier disease such as high-grade dysplasia and intramucosal adenocarcinoma (IMC) (3). Once diagnosed, however, there remains some controversy as to the best modality of treatment with the recent advent of advanced endoscopic techniques such as endoscopic mucosal resection (EMR).
Esophagectomy has been the traditional treatment for patients with intramucosal adenocarcinoma in the setting of Barrett’s esophagus. This was based on the previous thought that up to 40% of patients with high-grade dysplasia or IMC will have concomitant invasive disease in their esophagus (4, 5). This risk is now seen as having been overestimated (6). Moreover, esophagectomy is associated with significant postoperative morbidity and mortality (7). Advanced endoscopic techniques such as endoscopic mucosal resection (EMR) have the potential to treat selected patients with early esophageal cancer while preserving the esophagus and avoiding a complex and morbid operation.
Early (T1) esophageal cancer is defined as tumours that do not extend beyond the submucosal layer of the esophagus. The AJCC staging system distinguishes between T1a tumours, which are limited to the mucosal layer, and T1b tumours, which extend into the submucosal layer (8). One of the limitations of esophagus-preserving endoscopic techniques is the potential for spread of adenocarcinoma into the regional lymph nodes (9, 10). With tumours limited to the mucosa (T1a), the risk of lymph node positive disease is very low at < 2% (11, 12). For tumours involving the submucosa (T1b), lymph node involvement can rise to up to 20%, but rates with superficial involvement of the submucosa (T1sm1) remains acceptable around 6% (13). Beyond this level of invasion, the propensity for lymph node positive disease favours esophageal resection.
Esophageal intramucosal carcinoma remains a relatively rare disease and there is currently little literature on the success rates and long-term outcomes associated with EMR in comparison to esophagectomy in this setting (14-16). The purpose of this study is therefore to investigate the transition of therapy from esophagectomy to EMR at our institution for IMC with respect to successful eradication rates, number of EMRs required, post-operative morbidity, and long-term recurrence and survival.