International consensus to define outcomes for trials of chemoradiotherapy for anal cancer (CORMAC-2): Defining the outcomes from the CORMAC core outcome set

Abstract IntroductionAnal cancer is rare, but its incidence is increasing. Chemoradiotherapy is the primary treatment modality. Outcomes used in anal cancer trials vary which hinders evidence synthesis. Using a systematic review, patient interviews and a 2-stage Delphi consensus survey, the first CORMAC project brought together patients and healthcare professionals from across the world to agree shared priorities and make sure that studies of chemoradiotherapy treatments for anal cancer report outcomes that are meaningful to patients and health care professionals. CORMAC-1 established an internationally ratified core outcome set (COS) of 19 outcomes across 4 domains. These 19 outcomes are an agreed minimum that all clinical trials in chemoradiotherapy anal cancer trials should report. CORMAC-2 is the next phase which seeks to reach international agreement on the definitions for the 11 core outcomes in the domains of disease activity and survival. Agreeing definitions for these core outcomes will facilitate utilisation of the core outcome set, increasing outcome standardisation across trials thereby increasing the quality of data available for clinical decision-making and ultimately enhancing patient care.MethodsThe original CORMAC systematic review will be updated, focusing on 2 of the 4 COS domains, disease activity and survival domains. An international steering committee composed of international anal cancer trial experts will be formed. The committee will review the updated search results to develop a 2-stage Delphi consensus survey. The survey will be publicised through conferences, email lists, domestic and international bodies and will target healthcare and allied healthcare professional involved in the design, running, recruitment and publication of anal cancer trials. Following the 2-stage survey, a stakeholder meeting composed of the steering committee and selection of survey participants will ratify the results and agree a final set of core outcome definitions.Ethics and disseminationCORMAC-2 results will be disseminated through journal and conference publications to inform clinical teams and patient support groups to raise awareness and implementation of the core outcome set. Results will feed into the DECREASE study and it is registered with the Core Outcome Measures in Effectiveness Trials (COMET) initiative (1,2). As per the University of Manchester ethic decision tool, no ethical approval is required. Further information is available at https://cormacstudy.wordpress.com.