Development of an IDEAL Framework to Standardise Cytoreductive Surgery for Colorectal Peritoneal Metastases

Cytoreduction surgery (CRS) followed by hyperthermic intra-operative peritoneal chemotherapy (HIPEC) is a relatively new treatment for selected patients with peritoneal metastases of colorectal origin (PMCR). Data from outside of trials suggest that CRS and HIPEC improves survival compared with the current standard care (chemotherapy). The big challenge is to do trials in this setting - as the intervention is complex, and there are wide variations in the process and recording of outcomes. If trials can confirm the findings from non-randomised studies there are an estimated 1000 to 2000 patients who may benefit from this intervention in the UK each year. The aim of this study is to develop a framework which can be used to undertake a randomised trial in patients with PMCR suitable for CRS with or without HIPEC. The investigators will address this using the principles of the IDEAL (Idea, Development, Evaluation, Assessment \& Long term study) framework. Here, a pre-trial feasibility study will be performed between the two national peritoneal tumour treatment centres (Manchester and Basingstoke). This study is designed as such that it will take place over the following four stages: Stage 1. Comparing the treatment data from 100 operations from each of the two centres to identify which of the key components of the intervention differ as well as testing for differences in overall survival and recurrence free survival. Stage 2. Identifying sources of these differences by selecting up to 25 patients and investigating the variation in the way surgeons score key aspects of the procedure Stage 3. Development of a 'trial manual' with standardised definitions (to minimise any differences) Stage 4. Test how well people follow the manual in practice. After this study is complete, it will be possible to use the resulting trial manual to design future randomised trials to test the most suitable clinical question.