An evidence-based approach to the diagnosis and management of parastomal hernias reveals the lack of evidence on several topics, which need to be addressed by multicenter trials. Parastomal hernia prevention using a prophylactic mesh for end colostomies reduces parastomal herniation. Clinical outcomes should be audited and adverse events must be reported.

Background: Transanal total mesorectal excision (TaTME) for rectal cancer has emerged as an alternative to the traditional abdominal approach. However, concerns have been raised about local recurrence. The aim of this study was to evaluate local recurrence after TaTME. Secondary aims included postoperative mortality, anastomotic leak and stoma rates. Methods: Data on all patients who underwent TaTME were recorded and compared with those from national cohorts in the Norwegian Colorectal Cancer Registry (NCCR) and the Norwegian Registry for Gastrointestinal Surgery (NoRGast). Kaplan-Meier estimates were used to compare local recurrence. Results: In Norway, 157 patients underwent TaTME for rectal cancer between October 2014 and October 2018. Three of seven hospitals abandoned TaTME after a total of five procedures. The local recurrence rate was 12 of 157 (7⋅6 per cent); eight local recurrences were multifocal or extensive. The estimated local recurrence rate at 2⋅4 years was 11⋅6 (95 per cent c.i. 6⋅6 to 19⋅9) per cent after TaTME compared with 2⋅4 (1⋅4 to 4⋅3) per cent in the NCCR (P < 0⋅001). The adjusted hazard ratio was 6⋅71 (95 per cent c.i. 2⋅94 to 15⋅32). Anastomotic leaks resulting in reoperation occurred in 8⋅4 per cent of patients in the TaTME cohort compared with 4⋅5 per cent in NoRGast (P = 0⋅047). Fifty-six patients (35⋅7 per cent) had a stoma at latest follow-up; 39 (24⋅8 per cent) were permanent.Conclusion: Anastomotic leak rates after TaTME were higher than national rates; local recurrence rates and growth patterns were unfavourable.

Aim Parastomal hernia (PSH) is the most common complication of an end-colostomy and about one-quarter of patients need operative repair, which is often unsuccessful. A randomized trial was carried out to compare the results of using mesh or no mesh at the time of formation of a colostomy with the clinical identification of PSH as the primary outcome.Method In this two-centre randomized trial (Oslo University Hospital and Sykehuset Innlandet Hospital Trust, Norway), patients with rectal cancer undergoing open pelvic surgery were randomized to receive a retromuscular synthetic mesh (study group, n = 32) or no mesh (control group, n = 26) at the time of endcolostomy formation. Postoperative follow up was not blinded and included clinical examination and routine CT.Results The median period of follow up was 40 (range: 84) months. There were no differences in demographic variables or complications between the study and control groups. PSH developed in two patients of the study group and in 12 of the control group [OR = 0.04 (95% CI: 0.01-0.30) and hazard ratio 0.134 (95% CI: 0.030-0.603); P < 0.001]. The number needed to treat to avoid one PSH was 2.5 patients. CT demonstrated an increase over time in the size of the fascial orifice in patients with PSH without mesh prophylaxis, in contrast to a stable size in patients with mesh and in the control patients who did not develop PSH. ConclusionThe retromuscular insertion of synthetic mesh at the time of formation of an end-colostomy reduced the risk of PSH.

With PH, in comparison to IH treated with LVHR, no differences were observed regarding recurrence, protrusion or complication rates. Defect closure (raphe), when using absorbable suture, did not benefit long-term outcomes and caused a higher overall complication rate. (ClinicalTrials.gov number: NCT00455299).