Clinical Application Of Intraoperative Regional Lymphography Using Methylene Blue In Patients With Colorectal Cancer

Objective : To investigate the clinical value of intraoperative regional lymphography in the patients with colorectal cancer. Method: Twenty case with colorectal cancer underwent field lymph node after regional lymphography using Methylene blue and 5-Fu . According to the lymph node mapping, the excised lymph nodes were divided into three groups: 1.complete stain group (n=81), 2. partial stain group (n=67), 3. No stain group (n=56).All the excised nodes were examined by routine pathologic examination. Analyses clinical significance of lymph node mapping in operation of coloreatal cancer. Investigate relation of stain degree of lymph nodes and rate of node-positive. Results:204 lymph node were obtained after operation from 20 cases. 40.2 % of lymph nodes showed metastases. 59.8% is nonmetastases. The rate of lymph nodes metastases was 23.5% in complete stain group , 41.8% in partial stain group and 64.3% in no stain group, showing a significant difference between the three groups. Comparing complete stain group, partial stain group and no stain group, the metastatic rate of lymph nodes is significant difference. All show statistical significance. Conclusions: 1. Stain degree of regional lymph node have close relation with metastasis.The rate of metastasis in partial stain group and no stain group was higher than that in complete stain group. 2. Intraoperative lymphography is significant in operation of colorectal cancer and regional lymph nodes dissection, increase number of lymph node of colorectal cancer and perform routine pathologic examination, improving the detection of the rate of node-positive. Intraoperative injection of Methylene blue can be used to mark the primary tumor and define the lymphatic drainage so that adequate resection margins are obtained. The use of lymphatic mapping techniques improve staging accuracy in colorectal cancer. 3. Intraoperative regional lymphography is h-elpful for the complete field lymph nodes dissection, but is unable to detect the lymph nodes metastases. 4. Methylene blue and 5-Fu stain have both effects of lymphography and chemotherapy interposition in colectomy.