Detection of sentinel lymphatic region with activated carbon particles in lymph node dissection for colorectal cancer

Sentinel node navigation surgery (SNNS) for gastrointestinal cancer has been examined using various methods, but the SN concept has not been established. For 18 patients who had colorectal cancer without macroscopic nodal metastases, we had attempted to detect sentinel lymph nodes (SNs) with activated carbon particles and investigate the existence of nodal metastases histologically. SNs were detected in 17 of 18 patients. Thus activated carbon particles are a useful tracer for SN detection. Three patients had microscopic nodal metastases, and two had nodal metastases in SNs. Although the remaining patient was a false negative case which had nodal metastases in non-SNs only, the nodal metastases were within the sentinel lymphatic region (SLR) which includes SNs. It is considered possible to safely perform minimally invasive lymphadenectomy for colorectal cancer without macroscopic nodal metastases, by means of SLR dissection using activated carbon particles.