[New S3 guidelines on exocrine pancreatic cancer].

In order to guarantee a unified application of the R classification, the S3 guidelines were amended. With the introduction of the so-called CRM concept the special situation of ductal adenocarcinoma of the pancreas head can be taken into account. In contrast to the R classification, in the CRM concept lymph node metastases, lymph vessel and perineural sheath infiltration are taken into consideration. The distance of the tumor from the resection margins is particularly documented. Because of the prognostic significance of tumor-free lymph nodes, in future the lymph node ratio should be given. This is defined as the relationship of lymph node metastases to the total number of lymph nodes removed/examined.