Early squamous cell carcinoma of the oesophagus: the Japanese viewpoint

Abstract

In Japan, more than 90% of oesophageal malignancies are squamous cell carcinomas, and superficial and early carcinomas now account for about 40% and 20%, respectively, of all oesophageal carcinomas. Definition of early carcinoma has changed on the basis of new data. As of 2007, early carcinoma is defined as intramucosal carcinoma with or without metastasis. In the subclassification based on depth of cancer invasion, m1 and m2 carcinomas have no metastasis and are considered curable by endoscopic mucosal resection alone, whereas < 10% of m3 carcinomas and about 20% of sm1 carcinomas have lymph node metastasis. The relationship between various pathological findings and the incidence of lymph node metastasis has been reviewed. High-grade squamous dysplasia (squamous cell carcinoma in situ in Japan) requires surgical or endoscopic removal. Very minute carcinomas have recently been detected by magnifying endoscopy and/or narrowband imaging. Endocytoscopy could replace biopsy histopathological examination for diagnosis of oesophageal squamous cell carcinoma, and endocytoscopic diagnosis and endoscopic therapy may be performed simultaneously. As a result of advances in the development of endoscopes, pathologists are now expected to diagnose very minute lesions, < 1 mm in size, in the oesophagus.

18F‐Fluorodeoxyglucose positron emission tomography can be used to determine the indication for endoscopic resection of superficial esophageal cancer

“…The most important prognostic factor is lymph node metastasis 21. Among superficial esophageal cancers, the incidence of lymph node metastasis associated with T1a‐EP and T1a‐LPM tumors is very low (≤5%), that associated with tumors located within the muscularis mucosa (T1a‐MM) and tumors invading the upper third of the submucosal layer (T1b‐SM1) ranges from 10% to 20%, and that associated with tumors invading the middle and deeper third of the submucosal layer (T1b‐SM2, T1b‐SM3) may reach 50% 22. Therefore, T1a‐EP and T1a‐LPM tumors are absolute indications for ER.…”

Objective evaluation of visibility in virtual chromoendoscopy for esophageal squamous carcinoma using a color difference formula

“…15,16 The prevalence of Barrett's esophagus is lower in Japan than in Europe and the United States, and squamous cell carcinoma accounts for 90% of esophageal cancer. 1 The intrapapillary capillary loop ͑IPCL͒ is commonly observed in squamous cell carcinoma derived from the squamous epithelium with little or no glandular structure. Inoue 17,18 and Arima et al 19 showed that carcinoma gradually destroys normal microvessels with subsequent development of abnormal neovessels and avascular areas, leading to establishment of a method for diagnosis of the tumor margin and depth based on morphological classification.…”

“…The disease has a poor prognosis, and treatment of advanced carcinoma is especially invasive. 1 Improvements in techniques such as endoscopic mucosal resection ͑EMR͒ and endoscopic submucosal dissection ͑ESD͒ have provided more radical treatment for early stage esophageal squamous cell carcinoma, [2][3][4] but patients with invasion through the lamia propria into the muscularis mucosa or deeper may have lymph node metastases, 1 and an accurate estimation of the tumor depth is required prior to treatment. Kumagai et al invented a diagnostic method to determine tumor margins and depth by observing the intrapapillary capillary loop ͑IPCL͒ ͑microvessels at the surface of esophageal squamous carcinoma͒ using a magnifying endoscope.…”

Outcome of superficial squamous cell carcinoma of the esophagus: a clinicopathological study

“…Japanese pathologists report the diagnosis of squamous cell carcinoma in lesions, in which, Western pathologists would consider as dysplasia [20][21][22] .…”