The device used was removed from the market

Parastomal hernia (PSH) is one of the most frequent stoma complications with a high impact on patients' quality of life. Half of the stomas created each year are permanent and up to 50% of the patients will develop a PSH. PSH rates depend on the type of ostomy, ileo- or colostomy. End colostomy carries the highest risk for PSH (48%). PSH lead to recurrent pain, poor fitting appliance with leakage and therefore, skin irritation, and can also be complicated by strangulation or occlusion. The literature reports that 30% of patients with a PSH will require surgery. There are many different surgical procedures to repair PSH: primary fascia repair, relocation of the stoma or repair with various type of mesh. Despite the efforts done to improve the techniques, the incidence of recurrent PSH is up to 70% dependent of the used technique. Therefore, the idea of implanting a mesh at the time of initial stoma formation has lately been advocated. A new device, the KoringKM, which is a stomaplasty ring made of propylene, flexible and non-absorbable, was created. This study will try to prove that incorporation of the new stomaplasty ring at the time of stoma creation will diminish long-term PSH rate. This hypothesis will improve patient's quality of life and reduce costs associated with PSH.

All patients requiring a permanent ostomy (ileostomy or colostomy) for a malignant disease and fulfilling the inclusion criteria are eligible to participate in the trial. The patients will be randomized 24 to 48 hours prior to surgery after given written informed consent. The implantation of the Koring will be perfomed by experienced surgeons (expertise based, best team approach) who have already implanted the Koring (e.g. participated in the observational study) and/or have reviewed the video documentation. The surgeon will fill out the first form with the data of the patient and of the surgical procedure. The surgical wound will be daily examined. A second form will be fill out during the 30 post-operative days visit. The patients will be asked to inform the surgeon and/or investigator if any side event or suspicion of infection occurs after hospital discharge. The next follow-up visits will be at one and two years including a clinical examination and an abdominal CT. At this moment, the 3rd and 4th forms will be documented. All data will be anonymised and included in an Excel database.

Inclusion Criteria:

• Patients requiring permanent ostomy (ileo- or colostomy) for a malignant tumour with at least one year life expectancy
• Patient is able to cooperate
• Patient has given written informed consent
• Age equal or greater than 18 years

Exclusion Criteria:

• Life expectancy < 1 year
• Palliative surgery
• Benign disease
• Factors impacting on the ability to cooperate
• Mental disorders
• Pregnant or breastfeeding women
• Participation in another intervention trial with interference of intervention and outcome of this study
• BMI < 18