[Sentinel node biopsy in colorectal carcinoma--pilot study]

Sentinel lymph node biopsy is a widely accepted method for staging melanoma and breast cancer in indicated cases. However, the use of the method in colorectal cancer is under clinical investigation. The aim of the pilot study was to introduce the technique into the surgical practice in colon carcinoma, to determine the feasibility and potential problems and to evaluate the first experience.

Twenty patients with colon cancer underwent lymphatic mapping and sentinel node biopsy using blue dye, fluorescein or lymphoscintigraphy followed by standard surgical resection. The acquired sentinel nodes were investigated with both standard hematoxylin-eosin staining and immunohistochemical staining for cytokeratin.

Lymphatic mapping adequately identified at least one sentinel node (SN) intraoperatively or by a modified ex vivo technique in 20 patients (100%). The average number of SN was 1.5 (range 1-3), non-SN 13.6 (range 1-38) per patient. SN correctly predicted the regional lymphatic basin status in 14 cases (70%). The false negative rate was 40%. No patient has been upstaged on the basis of immunohistochemical staining.

Lymphatic mapping and sentinel node biopsy in colon cancer is feasible and safe method with a high SN identification rate. The role and significance of sentinel node biopsy in colon cancer is not as clear as its role in other tumors and remains controversial. Further large prospective studies with standardized techniques are needed to evaluate the potential benefit of this new method.