The development of the TNM classification of gastric cancer.

The first tumor, node, metastasis (TNM) classification for stomach tumors was published in the second edition of the TNM classification of malignant tumors in 1974 and was followed by additional editions up to the seventh edition published in 2010. In the Buffalo Meeting 2008 a harmonization between the Eastern (Japanese) and Western stomach tumor classification was achieved with only minor remaing differences. The present TNM classification of stomach tumors has been criticized but it can be considered generally accepted worldwide. For generating data based on this new TNM classification it is important to correctly use TNM and pTNM. The decions on therapy and the estimation of prognosis are based on TNM. New molecular factor studies will be correlated and based on the results of the TNM classification.