34 This has led to the adoption of endoscopic surveillance programs in many centers, but the actual benefit of surveillance in terms of cost and survival is still uncertain; it remains a controversial issue.35 The prognosis of established early esophageal adenocarcinoma is dependent on depth of invasion, which in turn determines the risk of lymph node metastasis. Nigro et al. showed that lesions confined to the mucosa had a 7% risk of

lymphatic click here metastasis, whereas 80% of those invading into muscularis propria had spread to lymph nodes.36 This study, as with other early studies of esophageal adenocarcinoma, was small and involved only 37 patients. Since then, larger studies have shown that tumors of the mucosa and the superficial 500 µm (SM1) of the submucosa provide negligible risk of lymph node metastasis. Westerterp and colleagues demonstrated lymph node metastasis in only 1/79 mucosal and SM1 adenocarcinomas, while Stein et al. reported no lymphatic spread in 53 similar cases.37,38 Early squamous cell carcinoma of the esophagus has been much more extensively studied, in part, due to the routine use of endoscopic ablation in Japan. Patients with early squamous cell carcinoma, no lymph node metastasis on computed tomography scan and no evidence of a second primary cancer have been shown to have a similar survival rate as the general population following endoscopic therapy.39 Mucosal and superficial

submucosal squamous cell cancers check details have an excellent prognosis due to low risk of lymph node metastasis. Tajima et al. reported on 240 patients after surgical resection of squamous cell cancer and showed that none of the mucosal or SM1 tumors had metastasized to lymph nodes.40 Stein and colleagues found a higher

rate of lymphatic spread of 7.7%, but this was based on just 26 mucosal/SM1 patients.38 Minimally invasive squamous cell esophageal cancer can be cured endoscopically; early detection is therefore crucial. In this context, the use of high-resolution video-endoscopy with adjuncts, such as chromoendoscopy and narrow-band imaging, are useful technologies. Although the cure rate is high, surveillance after endoscopic therapy is necessary due a significant risk of local MRIP recurrence.41 Data on endoscopic treatment of early esophageal adenocarcinoma are limited; therefore, evidence-based treatment recommendations are not yet available. Although the worldwide incidence of gastric cancer is slowly declining, it is still the fourth most common malignancy and the second most frequent cause of cancer death. Five-year survival is relatively good in Japan at 40–60%, compared to about 20% in Western countries. Over 50% of gastric cancers diagnosed in Japan are early lesions, and this may explain the overall better survival.30,42 Gastrectomy with regional lymph node dissection was formerly the only available curative treatment for early gastric cancer.