{"entity":{"id":"fiducial-markers","kind":"term","name":"Fiducial markers","aka":[],"tldr":"Tiny gold seeds or electromagnetic beacons placed in or near a tumour so the treatment machine can see exactly where it is each day.","summary":"Soft-tissue tumours in the prostate, liver, pancreas and lung are hard to see on the X-ray images used for daily setup. Fiducial markers implanted under ultrasound or endoscopic guidance show up clearly and let the couch be shifted to the tumour's true position; electromagnetic transponders report position continuously during the beam. Fiducials make stereotactic treatment of moving targets possible and are being joined by markerless tracking on MRI and with AI.","asOf":"2026-09-16","wikipedia":"https://en.wikipedia.org/wiki/Fiducial_marker","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Fiducial_marker"}],"tags":["radiation-wave1"],"related":[],"cancers":["prostate","hcc","pancreatic"],"sections":[],"technologies":["respiratory-motion-management","sbrt","imrt-igrt"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"notes":[],"category":"Procedures"},"route":"/terms/fiducial-markers/","neighbours":{"cancer":[{"id":"hcc","kind":"cancer","name":"Hepatocellular carcinoma","route":"/cancers/hcc/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"},{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"}],"technology":[{"id":"imrt-igrt","kind":"technology","name":"IMRT / IGRT (modern external beam)","route":"/technologies/imrt-igrt/"},{"id":"respiratory-motion-management","kind":"technology","name":"Respiratory motion management (4D-CT, gating, breath-hold, tracking)","route":"/technologies/respiratory-motion-management/"},{"id":"sbrt","kind":"technology","name":"SBRT / SABR (stereotactic radiotherapy)","route":"/technologies/sbrt/"}]}}