Application of carbon nanoparticles to mark locations for re-inspection after colonic polypectomy

Endoscopic surgery has been a novel treatment for colon polyps or even early colorectal cancer. However, the exact re-inspection after colonic polypectomy to detect the scar from polyp removal was difficult to be performed. In our previous study, colon cancer tattooed with carbon nanoparticles was easily found during surgery. We speculated that carbon nanoparticles could be used in exact re-inspection after colonic polypectomy.

To evaluate the efficiency of carbon nanoparticles for re-inspection after colonic polypectomy.

Twenty-four patients with precancerous lesion or early colorectal cancer that underwent colonoscopic polypectomy between October 2012 and December 2013 were enrolled in the study. Participants were divided into two groups. Group A patients were injected with carbon nanoparticles beneath the lesion sites 3 cm. Group B patients were not treated with nanoparticles. All patients underwent quarterly colonoscopies. Once the colonoscope was withdrawn from the site last time record, the time spent searching for lesions was recorded.

There were no significant differences between general conditions or lesion pathology between the groups. The time spent searching for lesions in Group B was much longer than that in Group A (13.67 ± 8.07 vs. 1.21 ± 0.39 min, P < 0.001). Carbon nanoparticles marked lesions for 12 months in some patients, and no adverse reactions were reported.

It was a small sample study.

Tattooing lesions using carbon nanoparticles suspensions is safe. The durability of dye enables lesions to be re-checked by colonoscopy or laparoscopy for up to 1 year.