The Fourth Edition of the UICC TNM Classification of Esophageal Carcinoma and Its Relevance for Comparison of International Data

Abstract

The TNM classification of the esophagus first appeared in the 1968 edition of the TNM Classification of Malignant Tumours [1]. In this edition, the regions, the extent of the primary tumor (T), regional lymph nodes (N), and distant metastases (M) classification of the esophagus was defined. This classification was made in 1966, with a trial period from 1967 to 1971. The TNM classification was revised and the second edition appeared in 1974 [2]. The revision was based on a proposal from the United States of America. This proposal was based on an analysis of more than 1000 patients with esophageal cancer that was conducted by the Task Force on the Esophagus of the American Joint Committee for Cancer Staging and End Results Reporting. The American system used three types of evaluation systems for classifying the extent of the disease, namely clinical, surgical evaluative, and post-surgical treatment classifications. Staging groups were defined in the second edition. In the third edition, published in 1978 [3], staging was changed from three to four groups, but the regions and the T, N, and M classification remained unchanged.