[TNM classification of carcinoma of the esophagus]

TNM classification of esophageal carcinoma was first described in the supplement to the first edition of the TNM classification in 1973. In the second edition, the classification was changed based on the data of 1,000 cases from the Task Force on Esophagus of American Joint Committee. In this edition, only the clinical classification was described, but the third edition included both clinical and post-surgical histopathological classification. But the criteria for T and pT classification differed. Before the fourth edition, specialists from Japan and the United States met in Hawaii in 1984. Data of the Japanese Nationwide Registration, including 7,742 patients from 1969 to 1978, were presented. After discussion based on these data, T was classified according to the depth of invasion, and perigastric lymph nodes were included in Regional Nodes in the fourth edition. Then, the TNM Research Committee of ISDE collected patient data of esophageal carcinoma from seven countries, and they were studied according to many factors. Based on these data, two proposals were made to the UICC TNM Committee. First, T1 should be divided into two categories: T1a, Tumor invasion of lamina propria; and T1b, Tumor invasion of submucosa. Second, metastases to distant lymph nodes should be grouped into the N classification instead of M classification. The first was accepted in the TNM Supplement of 1993, and the second will be accepted in the Fifth Edition, which will appear in 1997. It is important to accumulate data on many patients using the uniform registration form and to follow these patients very closely in the discussion of revisions to the TNM classification.