Clinical application of sentinel lymph node mapping in colon cancer: in vivo vs. ex vivo techniques.

Abstract

PURPOSE: Clinical usefulness of sentinel lymph node (SLN) mapping in colorectal

cancer remains controversial. The aim of this study is to evaluate the accuracy

of the SLN mapping technique using serial sectioning, and to compare the results

between ex vivo and in vivo techniques. METHODS: From February 2011 to October

2012, 34 colon cancer patients underwent SLN mapping during surgical resection.

Eleven patients were analyzed with the in vivo method, and 23 patients with the

ex vivo method. Patient characteristics and results of SLN mapping were

evaluated. RESULTS: The SLN mapping was performed in 34 patients. Mean age was

67.3 years (range, 44-81 years). Primary tumors were located in the following

sites: 13 in the right colon (38.2%) and 21 in the left colon (61.8%). SLN

mapping was performed successfully in 88.2% of the patients. There was no

significant difference in the identification rate between the two methods (90.9%

vs. 87.0%, P = 1.000). Both the mapping methods showed a low sensitivity and high

rate of skip metastasis. CONCLUSION: This study showed that SLN evaluation using

serial sectioning could not predict the nodal status with clinically acceptable

accuracy despite the high detection rate.