{"entity":{"id":"psa-kinetics","kind":"term","name":"PSA kinetics: PSA doubling time and PSA density","aka":["PSA doubling time","PSADT","PSA velocity","PSA density","PSAD","PSA kinetics","PSA rise","rising PSA","biochemical recurrence PSA threshold","PSA nadir","PSA response","PSA50","PSA90","PSA progression"],"tldr":"How fast PSA is rising matters more than its level: a doubling time under ten months after surgery or radiotherapy, or under nine months in castration-resistant disease, marks the men whose cancer is moving quickly and who benefit from earlier hormone therapy or a PSMA scan, while PSA density (PSA divided by prostate volume) helps decide who needs a biopsy at all.","summary":"What is measured: the rate of change of prostate-specific antigen and its concentration relative to gland size. How: doubling time is calculated by log-linear regression from at least three values over at least three months; density is PSA (ng/mL) divided by prostate volume (mL) on MRI or ultrasound, with 0.15 (0.10 with MRI) the usual threshold. Confounders: 5-alpha-reductase inhibitors halve PSA, prostatitis raises it. What a result changes: after radical prostatectomy a PSA of 0.2 ng/mL or more defines biochemical recurrence, and the EAU splits it into low and high risk by a doubling time of a year or less or a Gleason grade group of 4 or 5, which sets the urgency of salvage radiotherapy and whether hormone therapy is added; PSMA PET is positive in most men above 0.5 ng/mL; in non-metastatic castration-resistant disease a doubling time of ten months or less was the entry criterion for SPARTAN (apalutamide), PROSPER (enzalutamide) and ARAMIS (darolutamide), which lengthened metastasis-free and overall survival; a density above 0.15 with a PI-RADS 3 lesion tips towards biopsy, and density is an entry criterion for active surveillance (PRIAS 0.2 or less); in metastatic castration-resistant disease a 50 percent PSA fall (PSA50) is a trial endpoint, and a PSA under 0.2 at seven months of hormone therapy predicts long survival. Where it matters: biochemical recurrence, low-risk, non-metastatic castration-resistant and metastatic castration-resistant prostate cancer.","asOf":"2026-09-17","links":[],"tags":[],"related":["psa","psma-pet","mp-mri","gleason-grade-group","active-surveillance-term","castration-resistance","apalutamide","darolutamide","enzalutamide"],"cancers":["prostate-bcr","prostate-low-risk","prostate-nmcrpc","prostate-mcrpc"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"category":"Biomarkers"},"route":"/terms/psa-kinetics/","neighbours":{"term":[{"id":"active-surveillance-term","kind":"term","name":"Active surveillance and observation","route":"/terms/active-surveillance-term/"},{"id":"castration-resistance","kind":"term","name":"Castration-resistant prostate cancer (CRPC)","route":"/terms/castration-resistance/"},{"id":"gleason-grade-group","kind":"term","name":"Gleason score / Grade Group","route":"/terms/gleason-grade-group/"},{"id":"psa","kind":"term","name":"PSA (prostate-specific antigen)","route":"/terms/psa/"}],"technology":[{"id":"mp-mri","kind":"technology","name":"Multiparametric prostate MRI (PI-RADS)","route":"/technologies/mp-mri/"},{"id":"psma-pet","kind":"technology","name":"PSMA PET","route":"/technologies/psma-pet/"}],"drug":[{"id":"apalutamide","kind":"drug","name":"Apalutamide","route":"/drugs/apalutamide/"},{"id":"darolutamide","kind":"drug","name":"Darolutamide","route":"/drugs/darolutamide/"},{"id":"enzalutamide","kind":"drug","name":"Enzalutamide","route":"/drugs/enzalutamide/"}],"cancer":[{"id":"prostate-bcr","kind":"cancer","name":"Biochemical recurrence of prostate cancer","route":"/cancers/prostate-bcr/"},{"id":"prostate-low-risk","kind":"cancer","name":"Localised prostate cancer, very low and low risk","route":"/cancers/prostate-low-risk/"},{"id":"prostate-mcrpc","kind":"cancer","name":"Metastatic castration-resistant prostate cancer","route":"/cancers/prostate-mcrpc/"},{"id":"prostate-nmcrpc","kind":"cancer","name":"Non-metastatic castration-resistant prostate cancer","route":"/cancers/prostate-nmcrpc/"}]}}