CH40 is five percent saline solution of the activated carbon particles with 20nm in diameter. It can absorb a large amount of ethanol. CH40 reach to the regional lymph nodes immediately after local injection, visualize the regional lymph nodes black in color and release ethanol in the metastatic lymph nodes. As the direction of lymph nodes staining was coincident with direction of metastasis, rationalization of lymph nodes dissection could be performed as follows: 1) When lymph nodes metastasis are found along the lesser curvature, dissection of lymph nodes in the hepatoduodenal ligament should be carried out. 2) When lymph nodes metastasis are found in the infrapyloric region, dissection of lymph nodes along the splenic artery, in the hepatoduodenal ligament, at the posterior aspect of the pancreas, and at the root of the mesenterium should be carried out. 3) When lymph nodes metastasis are found along the left gastric artery, the common hepatic artery, or the splenic artery, dissection of para-aortic lymph nodes should be carried out.