Introduction: Esophageal cancer is one of the leading causes of cancer-related death worldwide. Its poor prognosis is related to an often late diagnosis. An earlier diagnosis and treatment however, is related to a better outcome. Early stage esophageal cancer can be diagnosed and treated endoscopically with minimally invasive techniques, which is associated with lower mortality and morbidity than surgery. Whether esophageal carcinoma can be treated endoscopically depends mainly on the risk of lymph node metastasis, which itself correlates to the invasion depth of the tumor. The question is whether endoscopy can accurately determine the invasion depth and thus the treatment modality.
Evidence acquisition: Articles used for this review were identified by searches of PubMed and references of relevant articles.
Evidence synthesis: Lesion morphology has some predictive value for the depth of invasion for squamous cell carcinoma (SCC) and esophageal adenocarcinoma (EAC). An intramucosal cancer generally has a flat appearance (Paris 0-IIa, 0-IIb,). By contrast, a submucosally invasive cancer often has an excavated (0-IIc, 0-III) and sometimes a polypoid morphology (0-I). In SCC, classification of surface vessels and intrapapillary capillary loops (IPCLs) allows accurate assessment of invasion depth. Generally, mucosal lesions are an indication for endoscopic treatment. However recent studies have shown that tumors with submucosal infiltration and low risk profile for metastasis can also be treated safely by endoscopic resection.
Conclusions: Endoscopic assessment allows a rather accurate estimation of invasion depth of early esophageal cancer. To determine the final treatment modality however the final histological staging obtained by endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) is crucial.