A Comparative Study on the WCRF International/University of Bristol Methodology for Systematic Reviews of Mechanisms Underpinning Exposure-Cancer Associations

Gokhan Ertaylan, Charlotte Le Cornet, Eline H. van Roekel*, Audrey Y. Jung, Martijn J. L. Bours, Antje Damms-Machado, Piet A. van den Brandt, Helena Schock, Theo M. de Kok, Jan Theys, Ilja C. W. Arts, Rudolf Kaaks, Matty P. Weijenberg, Renee Turzanski Fortner*

*Corresponding author for this work

Research output: Contribution to journal(Systematic) Review article peer-review

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The World Cancer Research Fund (WCRF) International and the University of Bristol have developed a novel framework for providing an overview of mechanistic pathways and conducting a systematic literature review of the biologically plausible mechanisms underlying exposure-cancer associations. Two teams independently applied the two-stage framework on mechanisms underpinning the association between body fatness and breast cancer to test the framework feasibility and reproducibility as part of a WCRF-commissioned validation study. In stage I, a "hypothesis-free" approach was used to provide an overview of potential intermediate mechanisms between body fatness and breast cancer. Dissimilar rankings of potential mechanisms were observed between the two teams due to different applications of the framework. In stage II, a systematic review was conducted on the insulin-like growth factor 1 receptor (IGF1R) chosen as an intermediate mechanism. Although the studies included differed, both teams found inconclusive evidence for the body fatness-IGF1R association and modest evidence linking IGF1R to breast cancer, and therefore concluded that there is currently weak evidence for IGF1R as mechanism linking body fatness to breast cancer. The framework is a good starting point for conducting systematic reviews by integrating evidence from mechanistic studies on exposure-cancer associations. On the basis of our experience, we provide recommendations for future users. (C) 2017 AACR.

Original languageEnglish
Pages (from-to)1583-1594
Number of pages12
JournalCancer Epidemiology Biomarkers & Prevention
Issue number11
Publication statusPublished - Nov 2017


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