[The new TNM classification and staging of stomach cancer]

A major revision of the TNM classification has been published in 1987. It eliminates previous differences between the UICC and AJCC versions. The new 4th edition of TNM has been accepted by all national TNM committees and enables international comparisons of data. For gastric carcinoma, the definitions for clinical and pathological primary tumor classification (T, pT) are now identical. The definition of regional lymph nodes has been revised, the stage grouping completely changed. It permits a more reliable estimation of prognosis. For the description of absence or presence of residual tumor after treatment the R classification is recommended. The reliability of classifications depends on methods used, therefore the respective requirements are discussed en detail.