Reduced Dissemination of Tumor Cells With Primary Ligation of the Inferior Mesenteric Vein in Rectal Cancer Patients.

Study Overview
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Brief Summary
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Effect of ligation sequence of the inferior mesenteric artery and vein on circulating tumor cells and survival in laparoscopic rectal cancer surgery: a prospective, multicenter, randomized controlled study (ARVECTS)

Detailed Description
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Several studies have demonstrated that the presence of circulating tumor cells (CTCs) in the peripheral blood can be a surrogate biomarker to predict recurrence and prognosis of rectal cancer. CTCs are released from the primary tumor into the bloodstream and have the potential to spread to distant sites and develop into micro-metastatic deposits. Numerous studies have demonstrated that surgical manipulation could promote the dissemination of tumor cells into the circulation. Theoretically, the potential risk of tumor cell dissemination can theoretically be minimized if the effluent vein was ligated first. However, there is no regulation in the current guidelines on the sequence of ligation of the inferior mesenteric artery and vein during rectal cancer surgery owing to a lack of sufficient evidence. This multi-center randomized controlled trial is to investigate effect of ligation sequence of the inferior mesenteric artery and vein on circulating tumor cells and survival in laparoscopic rectal cancer surgery

Official Title
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Effect of Ligation Sequence of the Inferior Mesenteric Artery and Vein on Circulating Tumor Cells and Survival in Laparoscopic Rectal Cancer Surgery: a Prospective, Multicenter, Randomized Controlled Study (ARVECTS)

Conditions
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Rectal Cancer

Intervention / Treatment
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* Other: Vein ligation first
* Other: Artery ligation first


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 18-75 years; Histopathologically confirmed as rectal adenocarcinoma(tumor located within 15 cm from the anal verge at colonoscopy); Patients with a stage I-III rectal cancer eligible for surgery and R0 resection is expected, patients with pelvic lateral lymph nodes metastasis are ineligible; ECOG score: 0-1; ASA score: I/II/III; Laparoscopic surgery; Informed consent. Exclusion Criteria: Patients who have received preoperative treatment (such as preoperative radiotherapy and chemotherapy); Receiving transanal total mesorectal excision (taTME), specimen extraction through natural lumen (NOSES) ; Recurrent rectal cancer; Simultaneous or metachronous colorectal cancer; Malignant tumors of other organs in the past 5 years or at the same time; The results of preoperative physical examination and imaging examination showed that: (1) the tumor involved the surrounding organs and required combined organ resection; (2) distant metastasis; (3) could not be resected at R0; Pregnant or lactating women; Patients with severe mental disorder; It is not suitable for patients undergoing laparoscopic surgery (such as extensive adhesion caused by previous abdominal surgery or inability to tolerate artificial pneumoperitoneum); History of unstable angina pectoris or myocardial infarction in the past 6 months; Have a history of cerebrovascular accident in the past 6 months; Systemic administration of corticosteroids within 1 month before enrollment; Taking folic acid related drugs within half a year before operation. Severe cardiac insufficiency (FEV1<50% of predicted values); Emergency surgery.

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vein ligation first<br>During this procedure, patients undergo laparoscopic rectal cancer surgery with the inferior mesenteric vein ligated first. | Other: Vein ligation first<br>* During this procedure, patients undergo laparoscopic rectal cancer surgery with the inferior mesenteric vein ligated first.<br>|
| Active Comparator: Artery ligation first<br>During this procedure, patients undergo laparoscopic rectal cancer surgery with the inferior mesenteric artery ligated first. | Other: Artery ligation first<br>* During this procedure, patients undergo laparoscopic rectal cancer surgery with the inferior mesenteric artery ligated first.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The changes of the level of circulating tumor cells in the peripheral blood | The changes of the level of circulating tumor cells in the peripheral blood before cutting the skin and after closing the abdomen | During the surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 3-year disease-free survival | The proportion of patients with no disease recurrence and metastasis after 3 years of surgery | From date of surgery, assessed up to 36 months | 
| 3-years overall survival | The proportion of patients who survived 3 years after surgery | From date of surgery, assessed up to 36 months | 
| Recurrence pattern | Recurrence patterns are classified into five categories at the time of first diagnosis: locoregional, hematogenous, peritoneal, distant lymph node, and mixed type | From date of surgery, assessed up to 36 months | 
| Blood loss | Blood loss during the surgery | During the surgery | 
| Operation time | Operation time | During the surgery | 
| Conversive rate | Conversive rate | During the surgery | 
| Number of lymph nodes collected | Number of lymph nodes collected | During the surgery | 
| Intraoperative morbidity and mortality rates | The intraoperative morbidity rates are defined as the rates of event observed within operation | During the surgery | 
| Postoperative morbidity and motality rates | This is for the early postoperative complication, which defined as the event observed within 30 days after surgery | 30 days | 
| Postoperative recovery course | Time to first ambulation, flatus, liquid diet and soft diet, duration of postoperative hospital stay and postoperative pain are used to assess the postoperative recovery course.Visual analog pain score method is used to evaluate the difference of postoperative pain degree | 10 days |