OBJECTIVETo evaluate the clinical application of carbon nanoparticles labeled lymph node staining in curative laparoscopic resection for colorectal carcinoma.

METHODSSixty-five patients undergoing curative laparoscopic resection for colorectal carcinoma in the Sun Yat-sen Memorial Hospital between September 2011 and June 2013 were prospectively enrolled and randomly divided into label group (with carbon nanoparticles, n=34) and control group (without carbon nanoparticles, n=31). Association between labeled lymph nodes and metastasis was analyzed. The total number of retrieved lymph nodes and lymph nodes metastatic ratio were compared between the two groups.

RESULTSMean number of retrieved lymph node of the label group was higher as compared to the control group (22.3±4.2 vs. 15.4±3.5, P<0.05). The total number of retrieved lymph node was 725 in the label group and 478 in the control group. Among them, lymph node < 5 mm accounted for 4.6% (33/725) in the label group, which was higher than 2.0% (10/478) (P=0.025) in the control group. The number of black stain label lymph node was 412, with black stain ratio 56.8% (412/725) in the label group. Metastatic ratio of black stain nodes was significantly higher than that of non-stain nodes [28.6% (118/412) vs. 19.5% (61/313), P=0.005].

CONCLUSIONSThe technique of carbon nanoparticles labeled lymph node staining in curative laparoscopic resection for colorectal carcinoma is easy and effective, which can increase the retrieved number of lymph nodes, especially for nodes < 5 mm. The black stain lymph nodes indicate higher risk of metastasis.