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Colorectal cancer (CRC) is the third most common cancer worldwide. Considering the high rate of incidence and mortality of CRC it is critical to determine the mechanisms of its dissemination. Although one of the better characterised tumours the prognosis of patients decreases dramatically when lymphatic metastasis occurs. In addition, the main important prognostic factor of CRC is the stage of tumour at the time of diagnosis, which is defined by the TNM system from the American Joint Committee on Cancer and the International Union Against Cancer. Therefore, during surgical treatment not only the primary tumour but also the draining lymph nodes have to be removed. From multivariate analysis it is known, that the number of examined lymph nodes is an independent prognostic factor. In this context, a prognostic relevance has been demonstrated not only for N0-, but also for N1and N2status. Adjuvant chemotherapy is recommended for stage UICC III colon cancer. It has been shown to reduce tumour recurrence and improve overall survival (Schmiegel, ReinacherSchick et al. 2008). The five-year survival rate drops significantly from the UICC stage I to IV (Table 1). Patients with an early stage tumour (UICC I) have an excellent prognosis and a five-year survival rate of 90%, compared to those with advanced tumours and lymph node metastasis, who have a five-year survival rate of 30-60%. Patients with distant metastasis have a five-year survival rate below 10%. Thus the prognosis of CRC is significantly influenced by the occurrence of lymph node metastasis and in addition to its value as a prognostic indicator it also affects the therapeutically management of patients. The understanding of molecular mechanisms involved in lymphatic metastases may open the door for future treatment strategies.