THE EXTENT OF LYMPH-NODE DISSECTION FOR COLON-CARCINOMA - THE POTENTIAL IMPACT ON LAPAROSCOPIC SURGERY

BACKGROUND. The surgeon is no longer able to palpate the mesocolon for lymph node metastases during laparoscopic colectomy. The extent of ly mph node dissection should be determined beforehand for cancer control . METHODS. The distribution of lymph node metastases was obtained by t he clearing method on colon carcinomas for 164 patients. RESULTS. For pericolic spread: for pT1 tumors, the distance from the primary tumor to a metastatic lymph node was 2.5 cm; for pT2, the distance was withi n 5 cm; for 97.0% of pT3 tumors with lymph node metastases, the distan ce was within 7 cm; for 93.3% of pT4 tumors with lymph node metastases , the distance was within 7 cm. For central spread: for pT1 tumors, th e rate of metastasis to central lymph nodes was 0%; for pT2, the rate of metastasis was 20.0% to intermediate lymph nodes; for pT3, the rate of metastasis was 30.6% to intermediate lymph nodes and 15.3% to main lymph nodes; for pT4, the rate of metastasis was 44.4% to intermediat e lymph nodes and 22.2% to main lymph nodes. CONCLUSIONS. Central lymp h node dissection is not required for patients with T1 carcinomas, but proximal and distal 3-cm margins of resection are required. For T2, c entral lymph node dissection that includes the intermediate lymph node should be performed, as well as 5-cm proximal and distal margins of r esection. For T3 and T4, central lymph node dissection including the m ain lymph node should be performed, as well as 7-cm proximal and dista l margins of resection. (C) 1997 American Cancer Society.