A Prospective, Randomized, Open, Parallel-controlled, Superior-efficacy Clinical Study of Radical Sigmoidectomy for Sigmoid Cancer Versus Radical Sigmoidectomy Combined with Indocyanine Green Fluorescence Imaging Lymphatic Tracing Dissection in the Treatment of Sigmoid Cancer

Inclusion criteria

• Age between 18 and 75 years old
• Confirmed sigmoid adenocarcinoma cancer pathologically
• Location of tumor: the sigmoid colon (descending colon from vertical to horizontal point) is the starting point of sigmoid colon, and the end point of sigmoid colon is at 15cm of anal margin.
• CT showed sigmoid colon cancer: T3-4a N+ M0
• Patients with non-local recurrence or distant metastasis;
• no multiple colorectal cancer;
• no neoadjuvant therapy;
• physical conditions such as heart, lung, liver and kidney function can tolerate surgery.
• Willing and able to provide written informed consent for participation in this study

Exclusion criteria

• Complicated with other malignant tumors or previous history of malignant tumors;
• patients with intestinal obstruction, intestinal perforation, intestinal bleeding, etc.;
• patients with tumor invasion or involvement of adjacent organs requiring combined organ resection;
• patients with poor anal function and incontinence before operation;
• patients with inflammatory bowel disease or familial adenomatous polyposis
• ASA grade ≥ IV and / or ECOG physical status score > 2;
• patients with severe hepatorenal function, cardiopulmonary function, blood coagulation dysfunction or severe underlying diseases unable to tolerate surgery;
• history of severe mental illness;
• pregnant or lactating women;
• patients with uncontrolled infection before operation;
• patients with other clinical and laboratory conditions considered by some researchers should not participate in this trial.