The new "Vienna classification" for epithelial neoplasias of the gastrointestinal tract. Advantages and disadvantages

A number of seminars have shown considerable differences between Japanese a nd Western pathologists in the the diagnostic differentiation of regenerati ve changes, dysplasia, and well differentiated adenocarcinoma in gastroente rological biopsy material. Lesions which most Western pathologists identify as "dysplasia" are often considered adenocarcinomas in Japan. A comparison of the biopsy-based diagnoses with those established in resected mucosa,ho wever, reveals appreciable diagnostic inexperience on the part of Western p athologists, with significant discrepancies between their diagnoses based o n biopsies and those based on resected material. Against this background, a new classification of epithelial neoplasias of the gastrointestinal tract was drafted on the occasion of the World Congress of Gastroenterology in Vi enna in 1998. By collapsing the diagnoses "high-grade adenoma/dysplasia, no ninvasive carcinoma (carcinoma in situ), and suspected invasive carcinoma" into a single category ("noninvasive high-grade neoplasia,"category 4),this scheme should largely eliminate the diagnostic discrepancies between Weste rn and Japanese pathologists. As with every classification,the Vienna class ification has its advantages and disadvantages;these are discussed here. Th e most important advantage of the Vienna classification is that the various categories are associated with different recommendations for further diagn ostic and therapeutic measures. This applies particularly to category 4, wi th the recommendation for only local treatment initially (endoscopic mucosa l resection or surgical excision). Since the introduction of the Vienna cla ssification the new WHO classification of neoplasias of the gastrointestina l tract has recently been published, in which the term dysplasia has been r eplaced by "intraepithelial neoplasia. "This means that the Vienna classifi cation needs to be modified accordingly.