{"entity":{"id":"percentage-gleason-pattern-4","kind":"term","name":"Percentage of Gleason pattern 4","aka":["percentage pattern 4","percent pattern 4","% pattern 4","pattern 4 percentage","proportion of pattern 4","Gleason pattern 4"],"tldr":"How much of the cancer in a biopsy is the more aggressive pattern 4 rather than the slower pattern 3. Two men can both be told grade group 2, one with 5 per cent pattern 4 and one with 45 per cent, and the number is what separates them.","summary":"Grade group 2 is Gleason 3+4=7: predominantly well-formed glands with a lesser component of poorly formed, fused or cribriform glands. 'A lesser component' covers everything from a trace to just under half, and the difference matters, because a man with a few per cent of pattern 4 is a candidate for active surveillance and a man approaching half is not. The Royal College of Pathologists made the percentage of Gleason pattern 4 a core item for core biopsies in its October 2024 revision of the UK dataset, following recommendations from both ISUP and the Genitourinary Pathology Society to report it in biopsies with grade group 2 and 3 disease. The dataset notes that methods of estimating the percentage vary between pathologists, so the figure is an estimate rather than a measurement.\n\nThe number also feeds the tools that turn a report into a decision. PREDICT Prostate uses the number of positive cores and the presence of intraductal or cribriform growth alongside the grade; the Cambridge Prognostic Groups separate grade group 2 from grade group 3 precisely because Gleason 3+4 and 4+3 behave differently; and the corpus's report reader asks for percentage pattern 4 as a field on the prostate form. If a report does not give it and the grade group is 2 or 3, it is a reasonable thing to ask the team for.","asOf":"2026-09-25","links":[{"label":"Royal College of Pathologists G084: dataset for histopathology reports for prostatic carcinoma, version 4, October 2024","url":"https://www.rcpath.org/static/8cc88604-2c8d-4df4-a99542df41c102af/G084-dataset-for-histopathology-reports-for-prostatic-carcinoma.pdf"},{"label":"Epstein et al., American Journal of Surgical Pathology 2016: the 2014 ISUP consensus conference on Gleason grading, and the grade group system","url":"https://doi.org/10.1097/PAS.0000000000000530"}],"tags":[],"related":["gleason-grade-group","active-surveillance-term","tumour-grade"],"cancers":["prostate","prostate-low-risk","prostate-intermediate-risk"],"sections":["diagnostics"],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["gleason-grade-group","cribriform-prostate-cancer","cambridge-prognostic-group"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"Pathology"},"route":"/terms/percentage-gleason-pattern-4/","neighbours":{"term":[{"id":"active-surveillance-term","kind":"term","name":"Active surveillance and observation","route":"/terms/active-surveillance-term/"},{"id":"cambridge-prognostic-group","kind":"term","name":"Cambridge Prognostic Group (CPG 1 to 5)","route":"/terms/cambridge-prognostic-group/"},{"id":"cribriform-prostate-cancer","kind":"term","name":"Cribriform growth pattern in prostate cancer","route":"/terms/cribriform-prostate-cancer/"},{"id":"gleason-grade-group","kind":"term","name":"Gleason score / Grade Group","route":"/terms/gleason-grade-group/"},{"id":"tumour-grade","kind":"term","name":"Grade","route":"/terms/tumour-grade/"},{"id":"intraductal-carcinoma-prostate","kind":"term","name":"Intraductal carcinoma of the prostate (IDC-P)","route":"/terms/intraductal-carcinoma-prostate/"}],"cancer":[{"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/"}]}}