Study on the No.253 Lymph Node Metastasis Patterns in Left-Sided Colon and Rectal Cancer

Study Overview
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Brief Summary
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The goal of this observational study is to learn about the the pattern of metastasis of the No.253 lymph node in colorectal cancer. The main questions it aims to answer are: 1. What are the risk factors for metastasis to the No.253 lymph node? 2.What is the prognosis for patients with metastasis to the No.253 lymph node? Patients with descending colon cancer, sigmoid colon cancer, and rectal cancer who undergo curative surgery with dissection of the No.253 lymph node are included in this study

Detailed Description
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The No. 253 lymph node (also named as apical lymph node of inferior mesenteric artery), as the third station in the inferior mesenteric artery lymphatic system, plays a vital role in the lymphatic circulation of the descending colon, sigmoid colon, and rectum. They serve as the last barrier for tumor metastasis from regional to distant sites. The definition of the range of the No.253 lymph node primarily follows the Japanese Colorectal Cancer Treatment Guidelines: the medial boundary is the segment from the root of the inferior mesenteric artery to the origin of the left colic artery, the caudal boundary is from the origin of the left colic artery to the intersection with the inferior mesenteric vein, the lateral boundary is the outer margin of the inferior mesenteric vein, and the cranial boundary is from the horizontal section of the duodenum to the beginning of the jejunum. However, the pattern of metastasis of the No.253 lymph node in colorectal cancer remains unclear, with most studies being retrospective and showing significant differences in results. Therefore, the investigator plans to be the first internationally to carry out this retrospective, registry-based study to determine the metastasis pattern to the No. 253 lymph node in colorectal cancer. This will provide definitive clinical evidence for D3 lymph node dissection in colorectal surgery.

Official Title
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Real World Registry Study on the No.253 Lymph Node Metastasis Patterns in Left-Sided Colon and Rectal Cancer

Conditions
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Colorectal Cancer, Lymph Node Metastasis

Intervention / Treatment
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* Procedure: Laparoscopic colorectal surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 18-75 years; Underwent laparoscopic left hemicolectomy, sigmoid colectomy, or rectal cancer radical surgery. Postoperative pathology confirmed as adenocarcinoma. No evidence of distant metastasis. Exclusion Criteria: Previous history of malignant colorectal tumors. Patients who have undergone multiple abdominal-pelvic surgeries. Patients undergoing emergency surgery due to complications such as intestinal obstruction, intestinal perforation, or intestinal bleeding. Surgery did not achieve R0 resection. Patients with concurrent other malignant tumors or multiple primary colorectal cancers. Patients unwilling to sign an informed consent or follow the study protocol for follow-up.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cohort of left-sided colorectal cancer<br>Patients underwent curative surgery with dissection of No.253 Lymph node | Procedure: Laparoscopic colorectal surgery<br>* Patients underwent laparoscopic left colectomy, sigmoid resection or rectal surgery according to the location of tumor.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Metastatic rate of No.253 lymph node | Pathologically confirmed tumor cell infiltration in the No.253 lymph node | About 10 days after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of harvested lymph nodes | Total number of lymph nodes dissected in the pathology report | About 10 days after surgery | 
| Incidence of postoperative complications | The proportion of short-term complications occurring within 30 days post-surgery | 30 days after surgery | 
| 5-year local recurrence rate | Local recurrence refers to the return of cancer in the same area where it originally developed, typically after treatment has been completed. | 5 years after surgery | 
| 5-year disease free survival rate | Disease free survival refers to the length of time after primary treatment during which a patient survives without any signs or symptoms of the cancer. | 5 years after surgery | 
| 5-year overall survival rate | Overall survival refers to the length of time from the primary treatment that patients are still alive. | 5 years after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Left-sided colorectal cancer, Lymph node dissection, No.253 lymph node