Lymph Node Mapping Via Flourescent Dye in Colon Cancer

The aim of the study is to evaluate whether lymph nodes draining the region of the carcinoma are located only inside the lines of standard resection or in some percentages are located outside as well. The visualized nodes draining the region of the carcinoma will be correlated to location, fluorescent yes/no and nodal positive/negative. The draining lymph nodes will be visualized using the fluorescent dye indocyanine green. The aim of the study is to evaluate whether lymph nodes draining the region of the carcinoma are located only inside the lines of standard resection or in some percentages are located outside as well. The visualized nodes draining the region of the carcinoma will be correlated to location, fluorescent yes/no and nodal positive/negative. The draining lymph nodes will be visualized using the fluorescent dye indocyanine green.

Participants with a diagnosed (andeno)carcinoma of the ascending, transverse, descending and sigmoid colon will be included. Preoperatively the participants will receive an indocyanine green(ICG) injection at four points around the tumour endoscopically. The ICG marking will take place one to five days prior to surgery. In the draining lymph nodes of the specific region the ICG will accumulate and thus visible via fluorescence-camera during the surgery. Intraoperatively, the precise locations of all fluorescent nodes will be documented photographically. A standard resection and lymph node dissection will be conducted, potential fluorescent nodes outside the standard resection lines will additionally be resected. The fresh specimen will then be measured, the fluorescent nodes marked and after the pathologic examination the nodes will be correlated to location, fluorescent yes/no and nodal positive/negative. The aim ist not the visualization of the Sentinel node or the directly draining lymphatic vessel but all the nodes draining the peritumorous region at the point of surgery.

Intervention group. Participants will receive a state of the art surgical procedure with additional lymph node mapping

Preoperatively the participants will receive an endoscopic marking at four points around the tumour with the fluorescent dye indocyanine green.

Picking ICG-positive lymph nodes ex vivo in unfixed specimen, sending ICG positive nodes separately to pathological examination

ICG-positive sites outside standard resection area will be "cherry picked", sent to pathological examination separatively.

Inclusion Criteria: histologically diagnosed carcinoma of the ascending, transverse, descending or sigmoid colon. Exclusion Criteria: not wanting to participate other carcinoma then adenocarcinoma endoscopic marking not possible