| ○ No | Evidence suggests that parastomal hernia substantially affects patients’ quality of life [2]. | |
| ○ Probably no |
| ○ Probably yes |
| • Yes | The healthcare question was prioritized by the European Hernia Society in view of ongoing debate about the relative effectiveness of prophylactic mesh for the construction of end colostomy and new evidence since the publication of previous guidelines. It was also prioritized in a members’ survery of the Association of Coloproctology of Great Britaine and Ireland [43] and a survey of the members of the American Society of Colon and Rectal Surgeons [44]. |
| ○ Varies |
| ○ Don’t know |
| Desirable effects |
| How substantial are the desirable anticipated effects? |
| ○ Trivial | Evidence demonstrates that mesh prophylaxis likely results in a reduction in parastomal hernia, and may result in little to no difference in the risk for surgery for parastomal hernia. There may not be any difference in effects compared to no mesh with regards to major complications, surgery for parastomal hernia and quality of life. | Surgery for parastomal hernia is an individual decision influenced by patients’ and surgeons’ decisions. Considering study demographics, the evidence summarized herein probably reflects practice variation in the wider European region. |
| ○ Small |
| • Moderate |
| ○ Large | Sensitivity analyses excluding the unpublished data of the PREVENT trial and the data of the PARTHENOPE trial on Bio-A mesh did not suggest different effects. Detailed statistical analyses are available in the online appendix. |
| ○ Varies |
| ○ Don’t know |
| Undesirable effects |
| How substantial are the undesirable anticipated effects? |
| ○ Large | No substantial evidence on undesirable effects was found. A scoping search on PubMed with the search syntax (mesh erosion) AND (*stomy OR stoma) did not suggest that mesh erosion is a pragmatic risk after parastomal hernia prevention with a prophylactic mesh. Randomized trials may not be the best study design to capture rare events. We performed an additional scoping search of observational studies (available in the online appendix), that did not identify any reported cases of mesh erosion with the use of a prophylactic mesh, albeit with mean/median follow-up duration between 11 and 60 months for 242 patients. | A minority of panel members suggested that undesirable effects were small rather than trivial. Harms related to the use of prophylactic mesh, (such as erosion, infection, stenosis) may exist, although published evidence does not report any substantial risk for harm. Under consideration of current published evidence, it is unlikely that the burden of any potential harm is substantial. |
| ○ Moderate |
| ○ Small |
| • Trivial |
| ○ Varies |
| ○ Don’t know |
| Certainty of evidence |
| What is the overall certainty of the evidence of effects? |
| ○ Very low | The certainty of evidence was low or moderate for outcomes of critical importance, therefore the overall certainty of evidence was considered to be low to moderate. | The panel considered that the certainty of the evidence is sufficient for most outcomes, including parastomal hernia, major morbidity and reoperation. However, quality of life is underreported, which does not allow for sufficient overall certainty on critical outcomes. There is no reason to suspect that patients with prophylactic mesh have a poorer quality of life compared to patients with mesh; nevertheless, it is crucial to collect additional evidence before supporting a strong recommendation. |
| • Low |
| ○ Moderate |
| ○ High |
| ○ No included studies |
| Values |
| Is there important uncertainty about or variability in how much people value the main outcomes? |
| • Important uncertainty or variability | Research suggests that parastomal hernia frequently affects patients’ quality of life to a substantial degree [2]. However, in a scoping search, no research was found that has focused on the value patients place on outcomes after construction of an end colostomy. | After we have presented the summary evidence in interactive form on GRADEpro to patient representatives, both agreed that the vast majority of patients would opt for prophylactic mesh. |
| ○ Possibly important uncertainty or variability | One of the patient representatives, who had an end colostomy for cancer, highlighted that it might be difficult for the patient to handle much information in addition to that related to their disease, the operation, the postoperative course and adjuvant therapy. |
| ○ Probably no important uncertainty or variability | The other patient representative, who was operated on for benign disease and was a medical professional, preferred being provided with sufficient information to decide on the intervention. |
| ○ No important uncertainty or variability | We do not anticipate that there would be substantial variability on the value patients place on quality of life, parastomal hernia, major morbidity and reoperation. | Both patient representatives reported that they would be substantially influenced by the opinion and preferences of their surgeon. Empirical evidence and the ongoing debate in surgical journals and social media, suggests that there is important variability in surgeons’ opinions and preferences. Therefore, it may be assumed that this variability will be reflected on patient decisions. |
| In addition, it was suggested that some older patients might not prefer a prophylactic mesh, whereas younger patients operated on for benign disease would prefer the intervention |
| Furthermore, it was noted that patients with specific values and beliefs would want to be informed about the material of a biological mesh. |
| Balance of effects |
| Does the balance between desirable and undesirable effects favor the intervention or the comparison? |
| ○ Favors the comparison | There was unanimous agreement that the balance of effects was in favor of prophylactic mesh. | With regards to the lack of difference between the intervention and the comparator in the effects on quality of life, it was suggested that, because the evidence was derived primarily from patients with cancer, the primary disease may dominate patients’ experience and their own-perception on quality of life. |
| ○ Probably favors the comparison |
| ○ Does not favor either the intervention or the comparison |
| • Probably favors the intervention |
| ○ Favors the intervention |
| ○ Varies |
| ○ Don’t know |
| Resources required |
| How large are the resource requirements (costs)? |
| ○ Large costs | Under consideration of a cost analysis [46] and a cost-effectiveness analysis [47], that takes into account the cost of the mesh, evidence suggests that prophylactic mesh results in substantial savings. | The intervention does not require additional resources with regards to personnel, and only moderate additional resources with regards to operation time, based on empirical evidence. |
| ○ Moderate costs ○ Negligible costs and savings• Moderate savings○ Large savings○ Varies○ Don’t know | No additional operating time was suggested by a meta-analysis of randomized trials [46]. |
| ○ Don’t know |
| Certainty of evidence of required resources |
| What is the certainty of the evidence of resource requirements (costs)? |
| ○ Very low | The quality of relevant research is at least moderate. | |
| ○ Low |
| • Moderate |
| ○ High |
| ○ No included studies |
| Cost effectiveness |
| Does the cost-effectiveness of the intervention favor the intervention or the comparison? |
| ○ Favors the comparison | “Synthetic mesh was less costly and more effective than biologic and no mesh to prevent PSH for all rectal cancer stages. At the willingness-to-pay threshold of £20,000/QALY, the incremental NMBs [95% CI] ranged between £3,412 [£3,384–£3,439] (stage-I) and £1,305 [£1,293–£1,316] (stage-IV) for synthetic vs. no mesh. Synthetic mesh was more cost-effective than no mesh unless the relative risk of PSH was ≥0.97 for stages I–III and ≥0.94 for stage-IV.” [47]. | |
| ○ Probably favors the comparison |
| ○ Does not favor either the intervention or the comparison |
| ○ Probably favors the intervention |
| • Favors the intervention |
| ○ Varies |
| ○ No included studies |
| Equity |
| What would be the impact on health equity? |
| ○ Reduced | No relevant evidence found. | The panel did not identify any substantial impact on equity. The additional use of operating room time was considered negligible. No special skills were thought to be required for the implementation on the intervention. The low cost of synthetic mesh also suggests no impact on equity. |
| ○ Probably reduced |
| • Probably no impact |
| ○ Probably increased |
| ○ Increased |
| ○ Varies |
| ○ Don’t know |
| Acceptability |
| Is the intervention acceptable to key stakeholders? |
| ○ No | Published [36, 48–53] and empirical evidence suggests that acceptability varies among surgeons. | The ongoing debate in surgical journals, social media, and empirical evidence, suggests that the intervention might not be acceptable to a substantial proportion of surgeons. |
| ○ Probably no | Furthermore, creation of the stoma is frequently been performed by trainees or junior surgeons, and the primary surgeon might not always oversee this part of the procedure. |
| ○ Probably yes | There were no concerns with regards to the acceptability of the intervention to patients and stoma care nurses. |
| ○ Yes• Varies○ Don’t know | No systematically collected published data were found on surgeons, patients and other stakeholders. | |
| Feasibility |
| Is the intervention feasible to implement? |
| ○ No | No relevant evidence identified. | The panel considered that the intervention is feasible to be performed, with no substantial challenges with regards to surgical technique, however some surgeons might need minimal training before performing the intervention. |
| ○ Probably no |
| • Probably yes |
| ○ Yes |
| ○ Varies |
| ○ Don’t know |
Surgical Focus 