Incorporating multiparametric MRI staging and the new histological Grade Group system improves risk-stratified detection of bone metastasis in prostate cancer.

There remains uncertainty on the need for bone staging in men with intermediate-risk prostate cancer. Current guidelines do not use mpMRI-staging information and rely on historic pathology grading.

We investigated the ability of mpMRI and the new Grade Group system to better predict bone metastasis status in a retrospective cohort study of 438 men with prostate cancer undergoing baseline mpMRI and isotope bone scintigraphy (BS).

Including mpMRI-staging information significantly increased the specificity of bone metastasis detection from 3.0% to 24.2% (P<0.01) and sensitivity from 89.2% to 97.3%. The new Grade Group score demonstrated progressive increase in bone metastasis rates (P<0.001). A novel risk-stratification model combining Grade Groups, PSA and mpMRI staging shows promise in predicting bone metastasis and could potentially reduce BS usage by 22.4%-34.7%.

Incorporating the new Grade Group system and mpMRI staging more accurately identified bone metastatic risk and suggests men with Grade Group ⩽2 and/or without radiological T3 disease could safely avoid routine bone staging.British Journal of Cancer advance online publication, 1 November 2016; doi:10.1038/bjc.2016.353

British journal of cancer. 2016 Nov 01 [Epub ahead of print]

David Thurtle, Ray C J Hsu, Madhurima Chetan, Artitaya Lophatananon, Rachel Hubbard, Vincent J Gnanapragasam, Tristan Barrett

Academic Urology Group, Addenbrooke's Hospital, University of Cambridge, Hills Road, Cambridge CB2 0QQ, UK., Cambridge University Clinical School, Cambridge CB2 0SP, UK., Institute of Population Health, University of Manchester, Manchester M13 9PL, UK., Department of Urology, Cambridge University Hospitals NHS Trust, Cambridge CB2 0QQ, UK., Department of Radiology, Cambridge University Hospitals NHS Trust, Cambridge CB2 0QQ, UK.