Squamous intraepithelial neoplasia of the esophagus: past, present, and future

Abstract

With regard to the esophagus, the term "squamous dysplasia" has been used in European countries, the United States, and China, while its use is controversial in Japan. Recently, "low-grade intraepithelial neoplasia" and "high-grade intraepithelial neoplasia" have been used as inclusive terms for dysplasia and carcinoma in situ in the World Health Organization classification. Endoscopically, it is often difficult to identify squamous intraepithelial neoplasia by conventional endoscopy, but application of iodine is useful for the diagnosis of such a lesion. In addition, new types of endoscopic techniques, including magnifying endoscopy, narrow-band imaging (NBI), and endocytoscopy are helpful to detect squamous intraepithelial neoplasia. NBI is very useful for identifying the intrapapillary capillary loop pattern. Regarding the pathological criteria of squamous dysplasia and squamous cell carcinoma, the views of Japanese and Western pathologists have differed significantly. Before the term "intraepithelial neoplasia" was introduced, severe dysplasia as diagnosed by Western pathologists was in fact the same as squamous cell carcinoma in situ or noninvasive carcinoma as diagnosed by Japanese pathologists. This problem has been solved by the introduction of the Vienna classification; however, there are still some issues that need to be resolved. One of them is the presence of basal layer type squamous cell carcinoma in situ, which is often underdiagnosed as lowgrade intraepithelial neoplasia by Western pathologists. Endoscopic treatments such as endoscopic mucosal resection and endoscopic submucosal dissection have recently become possible choices for squamous intraepithelial neoplasia; however, these techniques are not in widespread use in the West. We believe that a consensus meeting between Japanese and Western pathologists as well as endoscopists should be held promptly to reach a common ground for the nomenclature.

Asymptomatic Metastatic Esophageal Cancer Presenting Like Stroke—A Case Report

“…11 Incidentally, asymptomatic or symptomatic localized intraepithelial neoplasia may also be found, which when detected has excellent prognosis as compared to the more advanced stages of this disease. 12 At the time of presentation and diagnosis, the patient usually has at least one of the aforementioned symptoms, at least in the cases that we have seen in our experience. In at least 50% of cases, at diagnosis tumor has invaded/spread to nearby vital structures or metastasized, lung and liver being the most common locations.…”

An Update on Precancerous Lesions of Oral Cavity

“…[20,21] 4. WHO system: low, moderate, severe and carcinoma in situ. [22,23,24] A Modified Classification and Staging System for Oral Leukoplakia: A proposal for a modified classification and staging system for oral leukoplakia (OLEP) has been presented by Van der Waal el al, 2000 in which the size of the leukoplakia and the presence or absence of epithelial dysplasia are taken into account. Altogether four stages are recognized: LI -Size of leukoplakia < 2 cm L2 -Size of leukoplakia 2-4 cm L3 -Size of leukoplakia >4cm Lx -Size not specified P -Pathology PO -No epithelial dysplasia PI -Distinct epithelial dysplasia Px -Dysplasia not specified in the pathology report.…”

The New Era of Staging as a Key for an Appropriate Treatment for Esophageal Cancer

“…The NBI endoscope became the standard examination for the early detection of superficial esophageal cancer for identifying the intrapapillary capillary loop pattern. 13,14) However, the views of Japanese and Western pathologists have differed significantly. Before the term "intraepithelial neoplasia" was introduced, severe dysplasia as diagnosed by Western pathologists was the same as carcinoma in situ or noninvasive carcinoma as diagnosed by Japanese pathologists.…”