A caution regarding lymphatic mapping in patients with colon cancer

Background: The value of lymphatic mapping and sentinel lymph node biopsy in the treatment of colon cancer is controversial. The purpose of this study was to determine the accuracy of lymphatic mapping in patients with colon cancer. Methods: Forty-eight patients with colon cancer underwent lymphatic mapping and sentinel lymph node biopsy using isosulfan blue dye followed by standard surgical resection. The sentinel lymph nodes underwent thin sectioning as will as immunohistochemical staining for cytokeratin, in addition to standard hematoxylin and eosin staining. Results: In 47 (98%) patients, a sentinel lymph node was identified. Sixteen patients had lymph nodes containing metastatic disease, and in 6 patients the sentinel lymph node was positive for disease. In no patient was the sentinel lymph node the only site of metastatic disease. In 10 patients the sentinel lymph node was negative for disease, whereas the nonsentinel lymph nodes contained metastatic disease (false negative RATE = 38%) Conclusions: The role of lymphatic mapping and sentinel lymph node biopsy in colon cancer is not as clear as its role in other tumors. Further large prospective studies are needed to evaluate the accuracy and potential benefit of this procedure in patients with colon cancer