Lateral Lymph Node Dissection for Middle-low Rectal Cancer

Study Overview
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Brief Summary
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The investigators will perform CT three-dimension reconstruction for middle-low rectal cancer patients who have enlarged lateral lymph nodes to recognize the variance of pelvic vessels, by which to help reduce operative time and blood loss, localize the lateral lymph nodes, improve the lymph node harvested and positive rate. Besides, The investigators will label the vessels near the interested node to achieve node-by-node for further investigation.

Detailed Description
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CT three-dimensional reconstruction was performed for middle-low patients who had enlarged lateral lymph node before surgery. The main purpose is to recognize the track and variance of pelvic and iliac blood vessels. The investigators want to explore whether this method can help reduce operative time, unexpected injuries and blood loss, and The investigators also want to study whether it can help improve the lymph node harvested and positive rate during lateral lymph node dissection. Besides, The investigators want to perform node-by-node for enlarged lateral lymph node and CT three-dimensional reconstruction can help the investigators to localize and label the interested lymph node during operation. After node-by-node, The investigators can explore the accuracy of radiologists' and surgeons' judgement for lateral lymph node metastasis, and The investigators also want explore the best cut-off value of shorter diameter to predict lateral lymph node metastasis. Besides, The investigators want to perform texture analysis by combination radiology and pathology to find some useful parameters to predict lateral lymph node metastasis. The investigators also want to explore the feasibility of dissecting the unilateral visceral branch of internal iliac vessels when performing lateral lymph node dissection. The investigators will have a close follow-up for patients who have enlarged lateral lymph node but do not meet the criteria for lateral lymph node dissection. CT three-dimensional reconstruction can help The investigators recognize which parts' lateral lymph nodes have more potential possibility to metastasis and recurrence.

Official Title
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Prospective Study on Image-guided Internal Iliac Vessels Dissection and Node-for-node for Selected Lateral Lymph Node Dissection in Middles-low Rectal Cancer

Conditions
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Rectal Cancer

Intervention / Treatment
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* Radiation: CT three-dimensional reconstruction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1) confirmed rectal cancer; 2) tumor located less than 10 cm from the anus verge; 3) have enlarged lateral lymph on preoperative CT/MRI Exclusion Criteria: 1) patients who have severe liver or renal dysfunction;

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This group with intervention will be compared previous group without intervention.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: intervention group<br>All patients receive CT three-dimensional reconstruction before surgery. | Radiation: CT three-dimensional reconstruction<br>* All patients will receive CT three dimensional reconstruction before surgery<br>|
| No Intervention: control group<br>All patients did not receive CT three-dimensional before surgery | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| operative time | including total operative time and that for lateral lymph node | 2 year | 
| Blood loss | intraoperative blood loss | 2 year | 
| lateral lymph node harvested | lateral lymph node harvested | 2 year | 
| Accuracy of judgement for lateral lymph node metastasis | including radiologists' and surgeons' accuracy | 2 year | 
| Cut-off value of shorter diameter | The best cut-off value of shorter diameter for lateral lymph node dissection | 2 year | 
| vessels variances | The blood vessels variance of internal iliac vessels | October 1. 2018-December 31.2020 | 
| postoperative complication | including urinary and sexual function | 2 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| local recurrence rate | local recurrence rate | 3 year | 
| overall survival | overall survival | 3 year | 
| disease-free survival | disease-free survival | 3 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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node-by-node, lateral lymph node dissection, rectal cancer, CT three-dimensional reconstruction, internal iliac vessels dissection