The Vienna classification of gastrointestinal epithelial neoplasia

Abstract

Background: Use of the conventional Western and Japanese classification systems of gastrointestinal epithelial neoplasia results in large differences among pathologists in the diagnosis of oesophageal, gastric, and colorectal neoplastic lesions.

Aim: To develop common worldwide terminology for gastrointestinal epithelial neoplasia.

Methods: Thirty one pathologists from 12 countries reviewed 35 gastric, 20 colorectal, and 21 oesophageal biopsy and resection specimens. The extent of diagnostic agreement between those with Western and Japanese viewpoints was assessed by kappa statistics. The pathologists met in Vienna to discuss the results and to develop a new consensus terminology.

Results: The large differences between the conventional Western and Japanese diagnoses were confirmed (percentage of specimens for which there was agreement and kappa values: 37% and 0.16 for gastric; 45% and 0.27 for colorectal; and 14% and 0.01 for oesophageal lesions). There was much better agreement among pathologists (71% and 0.55 for gastric; 65% and 0.47 for colorectal; and 62% and 0.31 for oesophageal lesions) when the original assessments of the specimens were regrouped into the categories of the proposed Vienna classification of gastrointestinal epithelial neoplasia: (1) negative for neoplasia/dysplasia, (2) indefinite for neoplasia/dysplasia, (3) non-invasive low grade neoplasia (low grade adenoma/dysplasia), (4) non-invasive high grade neoplasia (high grade adenoma/dysplasia, non-invasive carcinoma and suspicion of invasive carcinoma), and (5) invasive neoplasia (intramucosal carcinoma, submucosal carcinoma or beyond).

Conclusion: The differences between Western and Japanese pathologists in the diagnostic classification of gastrointestinal epithelial neoplastic lesions can be resolved largely by adopting the proposed terminology, which is based on cytological and architectural severity and invasion status.

Figures

Figure 1

Extent of agreement between the viewpoints of 31 Western and Japanese pathologists; the diagnoses of (A) 35 gastric, (B) 20 colorectal, and (C) 21 oesophageal lesions are based on their currently used classification systems. R, reactive epithelium; L, low grade adenoma/dysplasia; H, high grade adenoma/dysplasia; S, suspected carcinoma; D, definite carcinoma; Tot, total. The group of pathologists with a Japanese viewpoint included nine Japanese, three German, one Austrian, and one British pathologist for the gastric diagnoses, nine Japanese, one German, one Austrian, one British, and one Korean pathologist for the colorectal diagnoses, and nine Japanese pathologists for the oesophageal diagnoses. For each organ system, Western pathologists who diagnosed suspected or definite carcinoma in a manner similar to the nine Japanese specialists in gastrointestinal pathology were considered (and most considered themselves) to have a Japanese viewpoint. For comparisons between Western and Japanese viewpoints the most common opinion was taken as each group's final diagnosis. Values of the kappa coefficient less than 0.4 represent poor agreement, values between 0.4 and 0.75 fair to good agreement, and values exceeding 0.75 excellent agreement.

Figure 2

Gastric lesion in a man aged 73 years. (A) Endoscopic picture of a small area of redness (arrowheads) in the corpus amid atrophic gastric mucosa. (B) Endoscopic picture after spraying indigo carmine, revealing a shallow depressed lesion (arrowheads). (C) Endoscopically resected specimen of this lesion that was diagnosed as high grade adenoma/dysplasia by most Western pathologists and as carcinoma (non-invasive carcinoma) by most Japanese pathologists. (D) Details of (C), showing budding of glands and a trabecular growth pattern that made several Western and Japanese pathologists suspect invasion into the lamina propria.

Figure 3

Extent of agreement between the viewpoints of 31 Western and Japanese pathologists; the diagnoses for (A) 35 gastric, (B) 20 colorectal, and (C) 21 oesophageal lesions are based on the five categories of the Vienna classification (table 1). C1, negative for neoplasia/dysplasia; C2, indefinite for neoplasia/dysplasia; C3, non-invasive low grade neoplasia; C4, non-invasive high grade neoplasia; C5, invasive neoplasia; Tot, total. For details on the comparisons between Western and Japanese viewpoints see the legend to fig 1.

Figure 4

Gastric lesion in a man aged 67 years. (A) Endoscopic picture of a slightly elevated lesion with a central depression (arrowheads) in the corpus. (B) Endoscopic picture after spraying indigo carmine, revealing the borders of the lesion more clearly (arrowheads). (C) Biopsy specimen of this lesion that was diagnosed as low grade adenoma/dysplasia by most Western pathologists and as carcinoma (non-invasive carcinoma) by most Japanese pathologists a few months before the meeting, but as category 4 (see classification in table 1) at the end of the meeting. (D) Details of (C), showing mild stratification but enlarged, rounded nuclei with prominent nucleoli.