Targeted radiation aims to cure prostate cancer while sparing healthy tissue

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age 40-80; Performance status 0-1; \>10 yr. life expectancy * Candidate for curative intended treatment * PSA \<20 ng/mL * Clinical stage T1c or T2a * Prostate anatomy suitable for focal brachytherapy * MRI identified index tumour (PI-RADS 3-5) with PCa confirmed on biopsy * A single index tumour focus with Gleason score 6 (\>10 mm maximum cancer-core length \[MCCL\]), Gleason score 3+4 (any MCCL) or Gleason core 4+3 (\<10 mm MCCL) * Systematic biopsies (≥10-12 cores) with no or low volume Gleason score 6 (3+3) PCa only * No severe urinary obstructive symptoms (e.g., urinary retention needing indwelling catheter) * Fit to undergo all procedures in the protocol * Included subjects should be able to participate in the planned follow-up (either on-site visits or telephone consultation accepted at specific time-points). * Included subjects should be able to read and understand the study details, and provide written informed consent to participate Exclusion Criteria: If any of the following criteria is present, the subject cannot participate in the study: * Not a candidate for curative intended treatment (e.g., other active malignancy except for non-melanoma skin-cancer, life-expectancy \<10 years, severe comorbidities etc.) * Prior surgical or radiation treatment of PCa; Prior transurethral-resection (TUR-P) is not an exclusion criterion. * Evidence/suspicion of extra prostatic extension on MRI * Tumour focus \>50% of one prostate half on MRI corresponding to stage \>T2a * Briganti 2018 score ≥7% * PCa with intraductal carcinoma, cribriform pattern, or small cell component * Any anatomical or clinical conditional not suitable for brachytherapy (e.g., imperforate anus, prostatitis, inflammatory bowel disease, severe calcifications etc.) * Any contraindication for prostate MRI (e.g., claustrophobia, pacemaker, estimated glomerular filtration rate ≤30 mL/min/1.73m2) * Reduction in MRI image quality that interferes with diagnosis caused by e.g., hip replacement surgery or other metal implants in the pelvic area. * Any medical condition precluding procedures * Any medication that may alter prostate morphology or alter MRI appearance (e.g., 5-alpha reductase inhibitors, prior androgen deprivation therapy \[ADT\]) * Subjects who are unwilling or unable to adhere to the study requirements (including treatment, required assessments and follow-up).