Técnica del ganglio centinela en el cáncer de colon

Introduction

The study of lymph nodes is the most important prognostic factor in colorectal cancer without metastasis. The sentinel lymph node technique identifies the lymph node that best predicts the patient's lymph node status and allows the performance of techniques of intensive study that improve staging. The aim of this study was to evaluate the efficacy of the sentinel lymph node technique in the staging of colon cancer.

Methods

We performed a prospective study of 45 patients preoperatively diagnosed with colon cancer in stages 0, i and ii. We carried out the sentinel lymph node technique ex vivo and with methylene blue. The sentinel lymph node was studied through multiple sections and immunohistochemical techniques in addition to hematoxylin and eosin staining. We performed a comparison with a control group of 45 patients who were studied through a single section and hematoxylin and eosin staining.

Results

We identified the sentinel lymph node in 98% of the patients, with a false-negative rate of 0. Overstaging was found to occur in 4.8 to 23.8% of the patients. In patients in whom less than 12 lymph nodes were studied, overstaging was between 10.5 and 36.8%.

Conclusions

Study of sentinel lymph nodes carried out ex vivo and with methylene blue predicts the lymph node status of patients with colon cancer. This technique overstages patients to stage iii, who will receive chemotherapy, which could improve their prognosis. The benefit of this technique is greater in patients, in whom less than 12 lymph nodes are studied.