{"entity":{"id":"ldr-seed-brachytherapy","kind":"technology","name":"Low-dose-rate seed brachytherapy","aka":[],"tldr":"Dozens of rice-grain-sized radioactive seeds are implanted permanently in the prostate in a single procedure and deliver their dose over months.","summary":"Permanent seed implantation uses iodine-125 or palladium-103 seeds placed through the perineum under ultrasound guidance in a one-off outpatient procedure. It is a curative option for low- and favourable intermediate-risk prostate cancer with control matching surgery and external radiotherapy, and is used as a boost in higher-risk disease (the ASCENDE-RT trial). The same seeds treat some lung and pancreatic tumours at surgery, and plaque brachytherapy with similar isotopes treats uveal melanoma.","status":"established","asOf":"2026-09-16","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Brachytherapy#Prostate_cancer"}],"tags":["radiation-wave1"],"related":[],"cancers":["prostate","uveal-melanoma"],"sections":["radiation"],"technologies":["brachytherapy"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["brachytherapy-term"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"notes":[],"principle":"Permanently implanted low-activity sources deliver a continuous low dose rate over weeks to months, exploiting repair differences between tumour and normal tissue.","strengths":["Single procedure","Excellent long-term control in low-risk prostate cancer","Preserves continence for most"],"limitations":["Urinary symptoms for months","Not suitable for large glands or prior TURP","Radiation safety precautions after implant"],"since":1980},"route":"/technologies/ldr-seed-brachytherapy/","neighbours":{"cancer":[{"id":"prostate","kind":"cancer","name":"Prostate cancer","route":"/cancers/prostate/"},{"id":"uveal-melanoma","kind":"cancer","name":"Uveal melanoma","route":"/cancers/uveal-melanoma/"}],"section":[{"id":"radiation","kind":"section","name":"Radiation Therapy","route":"/fronts/radiation/"}],"technology":[{"id":"brachytherapy","kind":"technology","name":"Brachytherapy","route":"/technologies/brachytherapy/"}],"term":[{"id":"brachytherapy-term","kind":"term","name":"Brachytherapy (internal radiotherapy)","route":"/terms/brachytherapy-term/"}]}}