The SCRIPT trial: study protocol for a randomised controlled trial of a polygenic risk score to tailor colorectal cancer screening in primary care
Sibel Saya,
Lucy Boyd,
Patty Chondros,
Mairead McNamara,
Michelle King,
Shakira Milton,
Richard De Abreu Lourenco,
Malcolm Clark,
George Fishman,
Julie Marker,
Cheri Ostroff,
Richard Allman,
Fiona M. Walter,
Daniel Buchanan,
Ingrid Winship,
Jennifer McIntosh,
Finlay Macrae,
Mark Jenkins,
Jon Emery
Affiliations
Sibel Saya
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Lucy Boyd
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Patty Chondros
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Mairead McNamara
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Michelle King
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Shakira Milton
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Richard De Abreu Lourenco
Centre for Health Economics Research and Evaluation, University of Technology Sydney
Malcolm Clark
IPN Medical Centres
George Fishman
Consumer Advisory Group, Primary Care Collaborative Cancer Clinical Trials Group
Julie Marker
Consumer Advisory Group, Primary Care Collaborative Cancer Clinical Trials Group
Cheri Ostroff
Centre for Workplace Excellence, University of South Australia
Richard Allman
Genetic Technologies/Phenogen Sciences
Fiona M. Walter
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Daniel Buchanan
Centre for Cancer Research, University of Melbourne
Ingrid Winship
Department of Medicine, Melbourne Medical School, University of Melbourne
Jennifer McIntosh
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Finlay Macrae
Department of Medicine, Melbourne Medical School, University of Melbourne
Mark Jenkins
Centre for Cancer Research, University of Melbourne
Jon Emery
Primary Care Cancer Research Group, Department of General Practice, Centre for Cancer Research, The University of Melbourne, Victorian Comprehensive Cancer Centre
Abstract Background Polygenic risk scores (PRSs) can predict the risk of colorectal cancer (CRC) and target screening more precisely than current guidelines using age and family history alone. Primary care, as a far-reaching point of healthcare and routine provider of cancer screening and risk information, may be an ideal location for their widespread implementation. Methods This trial aims to determine whether the SCRIPT intervention results in more risk-appropriate CRC screening after 12 months in individuals attending general practice, compared with standard cancer risk reduction information. The SCRIPT intervention consists of a CRC PRS, tailored risk-specific screening recommendations and a risk report for participants and their GP, delivered in general practice. Patients aged between 45 and 70 inclusive, attending their GP, will be approached for participation. For those over 50, only those overdue for CRC screening will be eligible to participate. Two hundred and seventy-four participants will be randomised to the intervention or control arms, stratified by general practice, using a computer-generated allocation sequence. The primary outcome is risk-appropriate CRC screening after 12 months. For those in the intervention arm, risk-appropriate screening is defined using PRS-derived risk; for those in the control arm, it is defined using family history and national screening guidelines. Timing, type and results of the previous screening are considered in both arms. Objective health service data will capture screening behaviour. Secondary outcomes include cancer-specific worry, risk perception, predictors of CRC screening behaviour, screening intentions and health service use at 1, 6 and 12 months post-intervention delivery. Discussion This trial aims to determine whether a PRS-derived personalised CRC risk estimate delivered in primary care increases risk-appropriate CRC screening. A future population risk-stratified CRC screening programme could incorporate risk assessment within primary care while encouraging adherence to targeted screening recommendations. Trial registration Australian and New Zealand Clinical Trial Registry ACTRN12621000092897p. Registered on 1 February 2021.
