Problems of pTNM classification of carcinoma of the stomach, colorectum and anal margin.

The pTNM classification of the UICC which has been valid since 1978 in some sections contains unclear definitions regarding gastro-intestinal tumours which require interpretation. In practice, this leads to variations in opinions and to a lack of uniform classification of tumour spread. The uniform measures which we have undertaken since 1969 at the University of Erlangen were described and explained. In the meantime these measures have been adopted by the DSK (German-Speaking National TNM Committee) and will to a large extent appear in the fourth edition of the TNM classification of the UICC.