The purpose is to assess and describe the oncological and functional outcomes following the introduction of curative targeted focal brachytherapy of prostate cancer in Denmark.

Men with a single MRI-identifiable prostate cancer index-tumour who fulfil inclusion criteria and are candidates for curative treatment. Eligible men will undergo curative intended targeted focal brachytherapy for treatment of histologically confirmed prostate cancer.

The intervention will include Low- (LDR) or High (HDR) dose rate targeted focal brachytherapy of prostate cancer. Collection of data on safety, morbidity, side effects and quality of life. Collection of clinical data on treatment efficacy, progression, and mortality.

All patients will have a follow up of 10-years for oncological outcome, 5-years for acute- and late toxicity-, and 2-years for functional outcomes, respectively. The follow up will include clinical data, MRI, confirmatory biopsies, and questionnaires at specific fixed time points pre-and post-operatively after 1-3 days, 4-weeks, 3-, 6--, 9-, 12-, 18-, and 24-months followed by every 6 months up to 5-yr and then every year up to 10-yr follow-up.

Anticipated number of patients is 50 and regular analysis and reporting will be performed continuously. The first short-term analysis will be after 18-months of follow-up after confirmatory MRI and biopsies, and the final reporting will be after 10-years follow-up in 2035.

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).