Endo-SPONGE for treating low rectal anastomotic leakage

Endo-SPONGE could treat anastomotic leakage in a relatively small number of carefully selected patients

4.1 The clinical experts advised that Endo-SPONGE was only suitable for treating a small selection of people. They explained that there were several key factors that informed decision making for treatment options for anastomotic leakage. These included the anatomy of anastomosis, the location and accessibility of the leakage, and the patients' general clinical conditions (specifically sepsis severity and their general health status).The clinical experts explained that, in their clinical experience, Endo‑SPONGE would be considered if:

The committee agreed that Endo‑SPONGE was indeed a 'niche' technology that could be considered for a relatively small number of patients. There was no evidence that define the criteria for patient selection. It concluded that a clearer understanding of the patient population who could benefit from Endo‑SPONGE was important. This should be included in future research objectives.

The benefits of Endo-SPONGE are not consistently defined and reported in the included studies

4.2 The definition of treatment success after Endo‑SPONGE varied between studies. It was most frequently defined as closure of the leakage cavity to less than 1 cm, or complete granulation and resolution of the cavity. Also, the reported stoma reversal rates varied widely between studies. The committee agreed that there was some evidence that Endo‑SPONGE may improve anastomotic leakage cavity healing and stoma reversal. However, the evidence was low quality with considerable variation in important clinical end points between studies. Also, a recently published systematic review was not included in the evidence review and its reported stoma reversal rate was considerably lower than the external assessment centre (EAC) pooled rate (Mahendran et al, 2020). The committee concluded that, while Endo‑SPONGE showed promise, the evidence base was not robust enough to support the claimed clinical benefits.

More evidence is needed to assess how acceptable Endo-SPONGE is to patients

4.3 The clinical experts advised that Endo‑SPONGE was likely to improve patients' quality of life. This was because it offers the possibility of stoma reversal and restoration of bowel function. However, only 2 studies reported patient outcomes that included patient acceptability (Riss et al. 2009) and functional bowel recovery (Huismann et al. 2019). In the clinical experts' experience, pain and discomfort were the 2 most reported adverse symptoms. Also, treatment with Endo‑SPONGE was only stopped because of pain in a small number of their patients. The committee concluded that, while Endo‑SPONGE may be poorly tolerated by some patients, there was uncertainty about how tolerable the treatment was. More real-world evidence is needed to understand the effect of Endo‑SPONGE on health-related quality of life and residual bowel function.

National databases could improve the evidence for Endo-SPONGE

4.4 The committee concluded that the overall quality of the current evidence was low with a high risk of bias. This was because of the retrospective study design, limited comparators and small sample sizes. The clinical experts explained that the patient groups for whom Endo‑SPONGE might be suitable would be small and carefully selected. So, it is unlikely that it would be practical to do a randomised controlled trial. However, they suggested that using a national database or clinical registry could help evaluate the clinical benefits of Endo‑SPONGE and define the most appropriate patient population. The committee agreed that further research with observational and real-world data would strengthen the evidence.

Managing anastomotic leakage is challenging without a clearly defined care pathway

4.5 The clinical experts noted that the rate of anastomotic leak after colorectal surgery in the UK is relatively low. One clinical expert estimated that the rate of anastomotic leak after colorectal surgery was approximately 6%. Around 10% to 15% of this would be leakage in the low rectal areas, for which Endo SPONGE can be used. The clinical experts recognised that there have been improvements in techniques for colorectal surgery such as stapling and robotics. This could help reduce the incidence of anastomotic leakage. However, it remains a serious complication after colorectal surgery in some patients. The clinical experts explained that the treatment care pathway for patients with anastomotic leakage varied across the NHS. It depends on local clinician experience as well as the facilities and resources available. The committee concluded that managing anastomotic leakage could be challenging without a clearly defined care pathway.

The Endo-SPONGE procedure is easy to learn but specific training is needed

4.6 The clinical experts advised that specific training is needed for the Endo‑SPONGE procedure but the procedure is easy to learn. The company provides free on-site training. The main challenge of getting clinical experience for this technology is the relative lack of patients for whom it can be used. A clinical expert explained that, in their organisation, Endo‑SPONGE may only be suitable for about 4 to 5 patients per year. Support from the company providing access to training such as simulation training may help to resolve this issue. The committee concluded that the Endo‑SPONGE procedure is easy to learn but specific training is needed.

Comparing Endo-SPONGE and percutaneous drainage may not be appropriate because they are likely to be used in different clinical scenarios

4.7 Both the company and the EAC did an indirect cost comparison of Endo‑SPONGE with percutaneous drainage for treating anastomotic leakage. However, the clinical experts advised that this comparison may not be appropriate. Alternative comparators such as the placement of a trans-rectal or trans-anal drain may be used for leaks after a low rectal anastomosis. Patients who can have treatment with either Endo‑SPONGE, a trans-anal drain or a percutaneous drain may have different clinical and anatomical characteristics. The committee understood that trans-rectal and trans-anal drains are surgical alternatives for treating anastomotic leakage and that the decision problem covered all surgical techniques. The committee concluded that Endo SPONGE and percutaneous drainage are likely to be used in different clinical scenarios. A like-for-like comparison between Endo SPONGE and trans-anal and trans-rectal in people with similar clinical and anatomical characteristics is needed.

The cost consequences of Endo-SPONGE are uncertain

4.8 There were 3 clinical scenarios modelled by the EAC. Of these, the clinical experts agreed on a scenario that most reflected clinical practice. This was the one in which the first assessment and Endo‑SPONGE insertion was done in an operating theatre under general anaesthesia, with sponge changes done in an outpatient setting under local anaesthesia or light sedation. The clinical experts also added that, in their experience, endoscopy is not needed to insert Endo‑SPONGE, because of how close the leakage cavities are to the anal verge. The committee noted that in the cost modelling, the main cost drivers were reoperation rates and rates of avoiding costs associated with a permanent stoma. However, a wide range of values for these important clinical parameters were reported in the studies. The committee concluded there were significant uncertainties related to the cost consequences of using Endo‑SPONGE.

Endo-SPONGE shows promise and further research is needed

4.9 Endo-SPONGE shows promise for treating anastomotic leakage, but further research is needed to help define the clinical and cost benefits. This research should address the uncertainties around patient selection. It should also evaluate the effect of avoiding further surgery and the rates of stoma reversal and bowel function restoration for Endo‑SPONGE and other treatments. This research should include patient-reported outcome measures to explore patient experience and the acceptability of this technology.