Award Title: ExtraPeritoneal End Colostomy Trial (ExPECT): Feasibility phase
Funder: Health and Care Research Wales (Welsh Government)

Abstract: Background
Parastomal hernia (PH) is a common complication of stoma formation. 100,000 people in the UK have stomas. Prevalence of stomas is growing as the population ages and cancer survival improves.
Stoma appliances cost £230 million/year. PH increases the cost of stoma care due to frequent leaks, skin problems, specialist appliances and nursing care. Parastomal hernias are known to have a significant impact on quality of life. Evaluating a technique to improve symptoms and quality of life is the focus of the proposed research.


Surgical repair of PH is challenging, requires the use of mesh and carries a high risk of complications and recurrence. The most serious complications of PH is bowel strangulation and obstruction. The ACPGBI have highlighted PH as an immediate research priority.


Several meta-analyses demonstrate a reduction in PH formation with mesh prophylaxis, but are limited by heterogeneity of techniques, mesh and endpoints. The largest RCT available to date does not show any benefit from prophylactic mesh placement. There are continued concerns regarding mesh related complications (infection, erosion, chronic pain), and use of mesh adds significantly to the cost of the index operation. As a result, in the latest guidance, NICE does not recommend mesh prophylaxis.


We propose a non-mesh prophylactic surgical technique to prevent parastomal hernia using an extraperitoneal (EP) approach. High quality data on EP colostomy formation are presently lacking but case series suggest equivalent rates of hernia prevention to mesh prophylaxis. In their recent review the ACPGBI Parastomal Hernia Group 2018 concluded that there was insufficient evidence to ascertain whether EP stoma construction reduces PH. As such there is a pressing need for a randomised controlled trial of EP colostomy formation compared with the standard transperitoneal (TP) technique.


Aims
The proposed study aims to test the feasibility of progression to a multicentre randomised controlled trial to evaluate EP colostomy formation to prevent PH and improve quality of life.


Plan
The feasibility study will be conducted across three sites. 60 patients will be randomised to either EP route or the standard TP route for end colostomy formation. Participants will be followed up at 6 weeks, 6 months and at 1 year. The proposed primary endpoint is the Colostomy Impact Score.
Other patient reported outcome measures known to be associated with parastomal hernia will be collected, as well as global quality of life (EQ-5D) at baseline and at follow up.


Data will be entered onto a web-based database at the three centres, and collected and analysed centrally.


Progression will be feasible if it is demonstrated that:
1.Patients and surgeons will recruit/participate in a trial 2.Patients are able to complete and return questionnaires
3.Surgeons are trained to perform the standardised EP technique 4.Data are co-ordinated across sites
5.Patients are followed up effectively


Summary/benefits
At the end of the feasibility study we will have demonstrated proof of principle for the infrastructure of a randomised clinical trial. The study will provide invaluable information on the recruitment rate, reproducibility of the technique and the appropriateness of the endpoint measures. This will allow the methodology to be refined and inform the design of a multicentre randomised controlled trial towards reduction of the global morbidity and cost of PH.

Lay Abstract: This study will test a surgical method of making a colostomy (or stoma) to reduce the chances of a hernia (or bulge) forming near it. The technique involves bringing the bowel out through a short tunnel underneath the muscles of the abdominal wall before attaching it to the skin as usual. This phase will test the study processes needed for a future larger trial to answer the research question of whether it can prevent hernia formation.

100,000 people in the UK have a bowel stoma. A commonly experienced problem is a hernia (or bulge) around the stoma site (a parastomal hernia). Such hernias can lead to leakage of faecal fluid, skin irritation, cosmetic problems from the bulge and chronic pain. All of these reduce patient’s quality of life. The most serious complications are bowel blockages or loss of blood supply, both requiring emergency surgery.

An effective surgical technique is required to prevent parastomal hernia from developing in the first place as repairs once they appear aren't always successful. Early studies suggest that using a technique to tunnel the stoma inside the thin inner layer of the abdomen (peritoneum) reduces the risk of PH. However, those studies are small and may not have followed patients for long enough to see if they had developed PH. Also, none of the studies asked about specific symptoms or did any assessment of the patients' quality of life after surgery.

We hope that a large scale clinical trial will tell us how well the tunnelled technique prevents hernias, reduces symptoms and improves quality of life. The aim of the proposed study is to test the running of such a trial. The work will test the willingness of patients to have the procedure and of surgeons to
perform it. We will also test the ability of questionnaires to record the symptoms and problems people have with hernias, and test the suitability of questionnaires which assess quality of life. We want to show that the questionnaires chosen are suitable to measure an improvement in quality of life with the alternative technique.

Research Activity Codes: 6.4 SURGERY
Health Categories: ORAL AND GASTROINTESTINAL