PROphylactic Mesh to Prevent Incisional Hernias at the Former Stoma Site: the PROMISS-trial (PROMISS)

Rationale: Approximately 7000 stomata are created in the Netherlands every year. The occurrence of a parastomal herniation is high, with a reported incidence of 4-48%. Also, the former stoma site is at increased risk for the development of an incisional hernia. A clinical incisional hernia rate of 30% is reported after stoma reversal. Herniation can cause pain, deformity and possibly incarceration, which results in a significant impact on the quality of life of the patient. The hypothesis of this study is that the use of a prophylactic mesh at the time of stoma formation leads to a lower incidence of incisional hernias after stoma reversal, an improved quality of life and therefore a possible cost reduction in healthcare. Objective: To evaluate the incidence of incisional hernias after stoma reversal after preventive mesh placement compared to no mesh placement. In addition, we aim to assess the effect of preventive mesh placement on the quality of life and the effect on healthcare cost reduction by avoiding re-intervention. Study design: A multicentre double blind randomized controlled trial with a total follow up of 24 months. Study population: Adults (18-99) undergoing bowel resection with the formation of a temporary stoma. Intervention: A preventive mesh will be placed using a sublay keyhole technique (pre-peritoneal, retromuscular) at stoma formation. The mesh will be left in situ after stoma reversal and the hole in the mesh will be closed, to prevent incisional herniation. Main study parameters/endpoints: Primary: Incidence of incisional hernias after stoma reversal Secondary: Quality of life, stoma related prolapse or parastomal herniation, cost effectiveness and mesh related complications. Nature and extent of the burden and the risks associated with participation, benefit and group relatedness: The standard surgical procedure for the treatment of parastomal hernias is used in a prophylactic fashion. As this is standard care in parastomal hernias the risks are minimal. The mesh that is used is CE approved. The burden of participation in this study is minimal for the patient all follow-up visits coincide with the regular visits for colorectal cancer. Hence, no extra outpatient department visits, and even no additional diagnostics nor other medical procedures that could potentially burden the patient, are required.

The intervention group will receive preventive mesh placement and in the control group no mesh is placed, the stoma is closed according to standard practise.

Incidence of incisional hernia Expressed in % ranging from 0-100%, a lower percentage is considered a better outcome.

Incidence of parastomal hernia Expressed in % ranging from 0-100%, a lower percentage is considered a better outcome.

Incidence of prolapse Expressed in % ranging from 0-100%, a lower percentage is considered a better outcome.

Incidence of mesh infection Expressed in % ranging from 0-100%, a lower percentage is considered a better outcome.

Incidence of wound infections Expressed in % ranging from 0-100%, a lower percentage is considered a better outcome.

Incidence of seroma Expressed in % ranging from 0-100%, a lower percentage is considered a better outcome.

Quality of life postoperatively assessed through questionnaires. - EQ-5D-5L (0-25), lower is considered a better outcome

Quality of life postoperatively assessed through questionnaires. - Carolina Comfort scale (0-40), lower is considered a better outcome.

Quality of life postoperatively assessed through questionnaires. - EORTC QLQ-CR29 (0-228), lower is considered a better outcome.

Time from start of the operation to finish (min), longer operation time can be an indication of a more complex procedure.

Time between creation of the stoma and its reversal, will be expressed in days. (minimum of 14 days to a maximum of 730 days). It will be measured from creation of stoma to reversal, which is 6 weeks on average, if the stoma is not reversed within 24 months the patient is excluded. For it will not be able to reach the primary endpoint. Delay of reversal of the stoma may indicate that patient condition or other patient related factors are not optimal.

Cost benefit analysis involving health cost and societal cost due to inability to participate in work. Lower health care cost are considered a better outcome, it is hypothesised that preventive treatment results in less cost by avoiding reoperations and readmission on the long term. Assessment will be performed using questionnaires; the iMCQ questionnaires for cost effectiveness analysis. The questions of the questionnaire will be analysed separately, for the questions range from yes/no questions to multiple choice or questions regarding number of days/ hours worked.

Cost benefit analysis involving health cost and societal cost due to inability to participate in work. Lower health care cost are considered a better outcome, it is hypothesised that preventive treatment results in less cost by avoiding reoperations and readmission on the long term. Assessment will be performed using questionnaires; the iPCQ questionnaires for cost effectiveness analysis. The questions of the questionnaire will be analysed separately, for the questions range from yes/no questions to multiple choice or questions regarding number of days/ hours worked.

Inclusion Criteria: Age ≥ 18 years Diagnosed with colorectal carcinoma Bowel resection following stoma formation, intended to be temporary. Elective surgery ASA-score I-III Signed informed consent Exclusion Criteria: Emergency operation Peritonitis (i.e. bowel perforation) Bowel obstruction A life expectancy of less than 2 years (distant metastasis i.e. located in the liver, peritoneum, lung, cerebral or bone) Earlier hernia repair with mesh placed in a 10cm proximity of the future stoma site. Chronic use of antibiotics Chronic use of immunosuppressive medication ASA-score IV or above Not able to sign informed consent Patient being unable to speak Dutch Patient allergic to one of the components of the mesh