Colorectal cancer lymph node staining by activated carbon nanoparticles suspension in vivo or methylene blue in vitro

Research performed at:

Department of Surgical Oncology, Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou 310009, Zhejiang Province, China.

The authors:

Hong-Ke Cai, Hai-Fei He, Wei Tian, Mei-Qi Zhou, Yue Hu, Yong-Chuan Deng.

AIM: To investigate whether activated carbon nanoparticles suspension (ACNS) or methylene blue (MB) can increase the detected number of lymph nodes in colorectal cancer.

METHODS: Sixty-seven of 72 colorectal cancer patients treated at our hospital fulfilled the inclusion criteria of the study which was conducted from December 2010 to February 2012. Seven patients refused to participate. Eventually, 60 patients were included, and randomly assigned to three groups (20 in each group): ACNS group (group A), MB group (group B) and non-stained conventional surgical group (group C). In group A, patients received subserosal injection of 1mL ACNS in a 4-quadrant region around the mass. In group B, the main artery of specimen was identified and isolated after the specimen was removed, and 2 mL MB was slowly injected into the isolated, stretchedand fixed vessel. In group C, no ACNS and MB were injected. All the mesentery lymph nodes were isolated and removed systematically by visually inspecting and palpating the adipose tissue.

CONCLUSION: Both activated carbon nanoparticles suspension in vivo and methylene blue in vitro can be used as tracers to increase the detected number of lymph nodes in colorectal cancer.