{"entity":{"id":"idea-prostate-per-lesion-mri-audit-before-focal-treatment","kind":"idea","name":"Publish a per-lesion miss rate for every prostate MRI service before it is allowed to guide focal treatment","aka":["per-lesion MRI audit prostate","whole-mount pathology audit focal therapy","MRI miss rate reporting"],"tldr":"Prostate MRI is good at telling you whether a man has a serious cancer and poor at telling you where all of it is. It missed at least one significant tumour in a third of men in the study that checked it against the whole removed prostate. Services that treat part of the gland, or follow men on imaging alone, are relying on the number they do not measure.","summary":"PROMIS established per-patient performance: sensitivity of 93 percent for clinically significant cancer against a template mapping biopsy reference, with specificity of 41 percent, which is what justifies using the scan to decide whether to biopsy. Johnson and colleagues measured per-lesion performance by co-registering scans with whole-mount pathology in 588 prostatectomy specimens: 45 percent of all 1,213 foci detected, 65 percent of clinically significant ones, at least one clinically significant focus missed in 34 percent of men overall and 45 percent of men with multifocal disease.\n\nThose two numbers answer different questions and are routinely quoted as if they answered the same one. A triage decision needs the first. Treating one part of the gland and leaving the rest, or following a man for years on imaging without biopsy, needs the second, and no service publishes it. Every centre performing radical prostatectomy after magnetic resonance imaging already generates the data required, because it has the scan and the whole gland. The proposal is that per-lesion sensitivity against whole-mount pathology, stratified by lesion size and grade, becomes a published quality metric, and a precondition for offering focal ablation or imaging-only surveillance.","asOf":"2026-09-25","links":[],"tags":["prostate-evidence"],"related":["idea-fund-device-technique-registry","idea-fund-ablation-versus-surgery-trials","idea-prev-prostate-as-triggered-biopsy","prostate-roadmap"],"cancers":["prostate","prostate-low-risk","prostate-intermediate-risk","prostate-high-risk"],"sections":["imaging","diagnostics","surgery"],"technologies":["mri","active-surveillance","prostate-screening-psa-mri"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["gleason-grade-group","prostatectomy","whole-mount-pathology","pi-rads","template-mapping-biopsy"],"trials":[],"people":[],"bottlenecks":["b-biomarker-validation","b-surgery-radiation-innovation","b-overdiagnosis","b-real-world-evidence","b-ai-validation"],"keyPapers":["paper-johnson-mpmri-individual-foci-eur-urol-2019","paper-ahmed-promis-multiparametric-mri-lancet-2017","paper-precision-mri-targeted-biopsy-nejm-2018","paper-klotz-active-surveillance-jco-2015"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"Per-lesion sensitivity of multiparametric magnetic resonance imaging against whole-mount pathology varies substantially between centres and readers, this variation is measurable from data centres already hold, and publishing it changes which centres offer focal therapy and imaging-only surveillance and reduces the rate of clinically significant cancer found outside the treated or monitored region.","rationale":"The per-patient and per-lesion figures differ by around 30 percentage points in the best available study, and the gap is exactly where focal therapy and imaging-only follow-up operate. Reader and protocol variation in prostate magnetic resonance imaging is well documented and is the standing argument for certification, but certification is currently based on reading test cases rather than on a centre's own outcomes. The audit proposed here requires no new imaging, no new pathology and no new consent beyond routine data use: the scan, the whole-mount specimen and the co-registration software all exist, and the comparison is already done retrospectively in research settings. Making it routine turns an unmeasured risk into a published number that patients and commissioners can act on.","test":"A multicentre audit in which every centre performing radical prostatectomy after multiparametric magnetic resonance imaging co-registers the pre-operative scan with the whole-mount specimen and reports per-lesion sensitivity for all foci and for clinically significant foci, stratified by lesion diameter, grade group, index versus non-index status and prostate-specific antigen density, with reader-level and scanner-level breakdown. Publish centre-level figures annually. Then test the consequence: a registry comparison of focal therapy outcomes (clinically significant cancer in the untreated gland at three years) between centres above and below the median per-lesion sensitivity. Two years to the first audit round.","maturity":"early-clinical","actor":"clinic","cost":"small","horizonYears":3},"route":"/ideas/idea-prostate-per-lesion-mri-audit-before-focal-treatment/","neighbours":{"idea":[{"id":"idea-fund-ablation-versus-surgery-trials","kind":"idea","name":"Device-agnostic public trials of ablation technologies against surgery","route":"/ideas/idea-fund-ablation-versus-surgery-trials/"},{"id":"idea-fund-device-technique-registry","kind":"idea","name":"Mandatory staged registries for new surgical techniques before wide adoption","route":"/ideas/idea-fund-device-technique-registry/"},{"id":"idea-prev-mri-first-prostate-screening-prs","kind":"idea","name":"MRI-first prostate screening with genetic pre-selection","route":"/ideas/idea-prev-mri-first-prostate-screening-prs/"},{"id":"idea-prev-prostate-as-triggered-biopsy","kind":"idea","name":"Prostate active surveillance without scheduled biopsies: MRI and blood tests decide","route":"/ideas/idea-prev-prostate-as-triggered-biopsy/"}],"roadmap":[{"id":"prostate-roadmap","kind":"roadmap","name":"Prostate cancer roadmap: from Huggins and the discovery that a cancer can depend on a hormone, through the PSA epidemic and what it cost, the androgen receptor drugs, the DNA repair subset and PSMA, to a 2032 registry watch","route":"/roadmaps/prostate-roadmap/"}],"cancer":[{"id":"prostate-high-risk","kind":"cancer","name":"Localised prostate cancer, high and very high risk","route":"/cancers/prostate-high-risk/"},{"id":"prostate-intermediate-risk","kind":"cancer","name":"Localised prostate cancer, intermediate risk","route":"/cancers/prostate-intermediate-risk/"},{"id":"prostate-low-risk","kind":"cancer","name":"Localised prostate cancer, very low and low risk","route":"/cancers/prostate-low-risk/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"section":[{"id":"diagnostics","kind":"section","name":"Diagnostics & Biomarkers","route":"/fronts/diagnostics/"},{"id":"imaging","kind":"section","name":"Imaging","route":"/fronts/imaging/"},{"id":"surgery","kind":"section","name":"Surgery & Interventional","route":"/fronts/surgery/"}],"technology":[{"id":"active-surveillance","kind":"technology","name":"Active surveillance","route":"/technologies/active-surveillance/"},{"id":"mri","kind":"technology","name":"MRI","route":"/technologies/mri/"},{"id":"prostate-screening-psa-mri","kind":"technology","name":"PSA and MRI-first prostate cancer screening","route":"/technologies/prostate-screening-psa-mri/"}],"term":[{"id":"gleason-grade-group","kind":"term","name":"Gleason score / Grade Group","route":"/terms/gleason-grade-group/"},{"id":"pi-rads","kind":"term","name":"PI-RADS (Prostate Imaging Reporting and Data System)","route":"/terms/pi-rads/"},{"id":"prostatectomy","kind":"term","name":"Radical prostatectomy","route":"/terms/prostatectomy/"},{"id":"template-mapping-biopsy","kind":"term","name":"Template mapping biopsy (transperineal template prostate mapping)","route":"/terms/template-mapping-biopsy/"},{"id":"whole-mount-pathology","kind":"term","name":"Whole-mount pathology","route":"/terms/whole-mount-pathology/"}],"bottleneck":[{"id":"b-ai-validation","kind":"bottleneck","name":"AI that is built but not validated or deployed","route":"/bottlenecks/b-ai-validation/"},{"id":"b-biomarker-validation","kind":"bottleneck","name":"Biomarkers are not validated or standardised","route":"/bottlenecks/b-biomarker-validation/"},{"id":"b-overdiagnosis","kind":"bottleneck","name":"Overdiagnosis and false alarms","route":"/bottlenecks/b-overdiagnosis/"},{"id":"b-surgery-radiation-innovation","kind":"bottleneck","name":"Surgery and radiotherapy cure most, get least","route":"/bottlenecks/b-surgery-radiation-innovation/"},{"id":"b-real-world-evidence","kind":"bottleneck","name":"Weak real-world evidence and registries","route":"/bottlenecks/b-real-world-evidence/"}],"paper":[{"id":"paper-johnson-mpmri-individual-foci-eur-urol-2019","kind":"paper","name":"Detection of individual prostate cancer foci via multiparametric magnetic resonance imaging","route":"/key-papers/paper-johnson-mpmri-individual-foci-eur-urol-2019/"},{"id":"paper-klotz-active-surveillance-jco-2015","kind":"paper","name":"Long-term follow-up of a large active surveillance cohort of patients with prostate cancer (Sunnybrook)","route":"/key-papers/paper-klotz-active-surveillance-jco-2015/"},{"id":"paper-precision-mri-targeted-biopsy-nejm-2018","kind":"paper","name":"PRECISION: MRI-targeted or standard biopsy for prostate cancer diagnosis","route":"/key-papers/paper-precision-mri-targeted-biopsy-nejm-2018/"},{"id":"paper-ahmed-promis-multiparametric-mri-lancet-2017","kind":"paper","name":"PROMIS: diagnostic accuracy of multiparametric MRI and TRUS biopsy in prostate cancer","route":"/key-papers/paper-ahmed-promis-multiparametric-mri-lancet-2017/"}]}}