The sentinel lymph node (SLN) significance in colorectal cancer: methods and results. General report

Colorectal cancer appears to be one of the most important malignancies in the world, with a survival rate depending on the TNM stage. The presence of lymph nodes metastasis indicates the necessity of adjuvant chemotherapy but exact classification of the N stage requires at least 12 lymph nodes to be pathologically examined. The sentinel lymph node (SLN) is considered to be the closest lymph node to the tumor, bearing the highest risk of malignant cells colonization. The main advantage of the sentinel lymph node mapping in colorectal cancer is identification and separate pathological examination of the nodes carrying the highest risk of metastasis. There are still open questions regarding the best method for sentinel lymph node mapping (in vivo or ex vivo), the factors influencing it, which substance is better for identification and which are the best histological methods and markers to be used. Numerous studies have discussed the quality and applicability of the method, but the importance of the SLN in colorectal carcinoma remains an open issue.