Chimney Trial of Parastomal Hernia Prevention

Study Overview
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Brief Summary
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Chimney trial is designed to compare the effectiveness and safety of specifically designated polyvinylidene fluoride mesh (PVDF, Dynamesh IPST) to controls in a multi center, randomized setting.

Detailed Description
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The European Hernia Society recommends the use of prophylactic mesh when permanent colostomy is made. The results of previous trials using keyhole technique are partially unsatisfactory. Specifically designed PVDF mesh used in this trial showed promising results in previous small trial. Chimney trial is designed to compare the effectiveness and safety of mesh group to controls operated with no preventive mesh in parastomal hernia prevention after laparoscopic or robotic-assisted abdominoperineal resection or low Haartman's procedure for rectal adenocarcinoma.

Official Title
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Chimney Trial - Randomized, Controlled, Multi Center Trial of Parastomal Hernia Prevention

Conditions
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Parastomal Hernia, Rectal Adenocarcinoma, Abdominoperineal Resection

Intervention / Treatment
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* Device: Intervention group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years or older Rectal adenocarcinoma with curative intent laparoscopic or robotic assisted abdominoperineal resection or low Hartmann´s operation and permanent colostomy Patient has a life expectancy of at least 12 months. Patient must sign Informed consent before any study procedures and agrees to attend all study visits Exclusion Criteria: Abdominoperineal resection or Hartmann's operation by laparotomy or conversion to laparotomy Complication requiring laparotomy during post surgery treatment at surgical ward after APR Patient with a comorbid illness or condition that would preclude the use of surgery (ASA 4-5). Patients with concurrent or previous malignant tumors within 5 years before study enrollment Patients with T4b tumors which impose a multi-organ resection Rectal malignancy other than adenocarcinoma Patient undergoing emergency procedures Planned rectal surgery along with major concomitant procedures (e.g. hepatectomies, other intestinal resections). Metastatic disease with no possibility of curative surgery Pregnant or suspected pregnancy Patients living geographically distant and/or unwilling to return for follow-ups or comply with all study requirements Active abdominal infection at the time of surgery Previous surgery at the colostomy site Language barrier or other reasons why informed consent is not possible

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Chimney trial is a prospective randomized controlled multicenter trial.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Intervention group<br>Polyvinylidene fluoride mesh used in this trial (Dynamesh IPST) is synthetic mesh with central tube to accommodate bowel tightly and designed to prevent and treat parastomal hernia. | Device: Intervention group<br>* Polyvinylidene fluoride mesh (Dynamesh IPST) is used on intraperitoneal onlay position to prevent parastomal hernia.<br>|
| No Intervention: Control group<br>Participants in control group are operated with no preventive mesh. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of parastomal hernia | Incidence of parastomal hernia at 12 months follow up | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of parastomal hernia at long term follow up | Incidence of parastomal hernia during 5 years of follow up | 5 years | 
| Surgical site infection rate | Surgical site infections measured by Clavien-Dindo Classification | 30 days | 
| Complications | Complications measured by Clavien-Dindo Classification | 30 days | 
| Stoma related complications | Stoma related complications measured by Clavien-Dindo Classification | 5 years | 
| Reoperation rate | Need for reoperations | 5 years | 
| Operative time | Operative time | 1 day | 
| Length of stay | Length of stay at the hospital | 30 days | 
| Rand 36 quality of life | Quality of life measured by Rand-36 quality of life questionnaire | 5 years | 
| Quality of life measured by Colostomy impact score | Quality of life measured by Colostomy impact score | 5 years | 
| Medico-economic substudy | Medico-economic substudy including both short and long term costs included in both groups | 5 years | 
| Radiological substudy of stoma distance | Distance of stoma from midline defined by umbilicus | 3 years | 
| Radiological substudy of adipose tissue thickness | Thickness of adipose tissue on computer tomography scan on contralateral site of stoma | 3 years |