The PRIM multi-centre study to refine and target early detection in prostate cancer using imaging and biomarkers

Principal Investigator: Professor Vincent Gnanapragasam, Department of Surgery

Funded by: Addenbrooke's Charitable Trust & the CRUK Cambridge Centre Urological Malignancies Programme

Published Paper: Clinical utility and cost modelling of the phi test to triage referrals into image-based diagnostic services for suspected prostate cancer: the PRIM (Phi to RefIne Mri) study.
BMC Medicine, published April 17 2020. DOI: 10.1186/s12916-020-01548-3

The Prostate Health Index, which combines total PSA (tPSA), free PSA and [-2]proPSA, has been shown to outperform tPSA for the prediction of prostate cancer on biopsy. The PRIM study (PHI in Refining MRI) is recruiting in five UK Centres, including the Department of Urology at Cambridge University Hospitals Trust. The study, led by Professor Vincent Gnanapragasam, determines how the test can be used to reduce and refine the need for expensive imaging tests, such as MRI, while increasing the detection of lethal prostate cancers. The target population was those men with a first referral for suspected new prostate cancer. PRIM represented one of the first multi-centre UK studies to combine a biomarker with modern MR imaging to refine early detection of prostate cancer and applied in real world clinical practice. The data published in 2020 showed that the use of the PHI as a triage test could reduce both imaging and biopsies needs by a quarter while maintaining diagnostic efficiency using two definitions of clinically significant prostate cancers. We further demonstrate that introducing the PHI is likely to be both the cheapest per referred patient and cheapest per net tumour detected allowing resources to be diverted to other needs.