[Tumor classification--present status and further developments]

Characterization of the individuality of a malignant tumor is needed for planning treatment and evaluating its results. The present classification of tumors is the result of long years of international effort, and is published as the WHO International Histological Classification of Tumors and the UICC TNM Classification of Malignant Tumors, 4th edition. For a number of tumor entities TNM classification is not yet available. A classification of liver and lung metastases is the aim of UICC studies, some of which have been initiated. The further development of tumor classification is focused on the identification of independent prognostic factors (prognostic indices and prognostic grouping), which apart from the TNM defined stage, have separate influence on the prognosis.