Is Routine Use of Sentinel Node Biopsy Justified in Colon Cancer?

Excerpt

Because lymph node metastasis predicts survival and recurrence in colon cancer (CC),1 decisions regarding adjuvant therapy are largely based on nodal status. Chemotherapy is not routine for node-negative CC because its toxicity and expense exceed its limited benefit in patients without evidence of nodal involvement. However, 25% of patients with node-negative CC will develop disease recurrence after surgical resection alone. This suggests that either the tumor staging system or the staging technique is inadequate. The sentinel lymph node (SLN) procedure is a selective sampling technique that can be used to ultrastage regional nodes. The SLN is the first node or nodes to receive lymphatic drainage from a primary tumor and thus the most likely nodal site of metastasis. Mapping, dissection, and focused examination of SLNs can identify occult nodal metastases that may increase the risk of recurrence. The tumor status of the SLN does not change the extent of resection because en bloc resection of the primary CC includes regional lymph nodes; however, results of SLN-based nodal ultrastaging can improve identification of candidates for adjuvant therapy of CC. …