Detection of isolated disseminated tumor cells of colorectal cancer in lymph nodes

The 5-year survival of patients with colorectal cancer UICC stage I and II ranges from 70 % to 80 %. Therefore, at least 20 % to 30 % of these patient s develop recurrent disease, caused by hematogenic or lymphogenic tumor cel l dissemination. Using immunohistochemical or molecular biological methods, disseminated tumor cells can be detected in lymph nodes in a high proporti on of patients in UICC stage I or II. The detection of disseminated tumor c ells could help to identify a subgroup of patients at risk for disease rela pse who could benefit from adjuvant therapy. Lymphogenic tumor cell dissemi nation seems to be a very common event in early colorectal cancer, precedin g hematogenic tumor cell dissemination. Although these observations appear to confirm the therapeutic importance of meticulous lymph node dissection, their prognostic relevance has yet to be determined in prospective studies.