The feasibility and reliability of sentinel node mapping in colorectal cancer

Sentinel node mapping (SNM) has been introduced in colorectal cancer (CRC) to improve staging by facilitating occult tumour cell (OTC) assessment in lymph nodes that are most likely to be tumour-positive. In this paper, studies on the feasibility and reliability of SNM in CRC are reviewed. A literature search was conducted in the National Library of Medicine by using the keywords colonic, rectal, colorectal, neoplasm, adenocarcinoma, cancer and sentinel. Additional articles were identified by cross-referencing from papers retrieved in the initial search. There is a large variation in identification rates and false-negative rates mainly due to the learning curve effect, differences in SNM technique and tumour stage. We conclude that SNM in CRC is technically feasible. Standardization of SNM procedures is mandatory to resolve the debate on the reliability of sentinel node status for predicting the tumour status of all lymph nodes. Only then can adjuvant treatment of patients upstaged by OTC detection in sentinel nodes be justified.