This video shows feasibilty and preliminary results of sentinel lymphnode (SL) analysis in laparoscopic colon resections for cancer. Twenty patients have been studied from March 2004 to December 2005. Before surgical dissection 2 ml of Patent Blu V dye were injected subserosally around the tumor with a 22 gauge spinal needle percoutaneously. The lymphnodes coloured were marked as sentinel with metallic clips and the operation was completed with standardized technique. All sentinel lymphnodes were examined by hematoxylin and eosin with multiple sections made at 50 micron intervals. Immunonhistochemical (IHC) evaluation was applied only to doubtful cases. Detection rate of SL was 100%, in one case was performed an "ex vivo" technique. Of the 20 patients seven (35%) had lymphnode metastases. One false negative case (14.3%) was registered. Two doubtful cases, evaluated with IHC, revealed isolated tumor cells. Accuracy, Sensitivity and Negative Predictive Value were respectively 95%, 85.7% and 92.8%. Laparoscopic lymphatic mapping in colon surgery is a feasible technique. The detection rate of SL reaches 100%, performing a salvage "ex vivo" technique. The false negative rate (14.3%), in this preliminary cases, may be reduced with selection of patients and exclusion of stage III disease.