Focal Salvage HDR Brachytherapy for the Treatment of Prostate Cancer

Radiation therapy is considered a standard treatment option for the management of localized prostate cancer. Among the 20-30% who recur, a proportion of them will present with an isolated local recurrence, meaning no distant metastases. If left untreated, it may serve as a source for subsequent metastases. Salvage options available for isolated local recurrence include; temporary or permanent implantation of radioactive seeds into the prostate, complete removal of the prostate gland, use of low temperatures to treat the disease, and high frequency ultrasound to treat the disease. There are risks of complications associated with all these treatments, and there is presently no consensus as to which treatment is the best. Therefore, the aim of this pilot study is to look at the feasibility and toxicities of focal treatment of the prostate using temporary implantation of radioactive seeds into the prostate which the investigators hope will be less since the entire prostate is not treated.

Sex

Male

Minimum age

18 Years

Inclusion Criteria:

* Biopsy-confirmed locally recurrent prostate adenocarcinoma \> 30months after the completion of XRT, SBRT, LDR or HDR brachytherapy boost with XRT, or LDR or HDR brachytherapy as monotherapy by a stereotactic transperineal biopsy
* Staging T2-weighted, DWI and DCE-MRI that demonstrates solitary recurrence confined to prostate, and correlates with stereotactic transperineal biopsy
* Staging CT or MRI (abdomen and pelvis) and bone scan are negative for metastases
* American Urological Association Symptom Index Score (ie. IPSS) \< 15
* Baseline (post-XRT) serum PSA \< 10 ng/mL
* Prostate volume as measured by transrectal ultrasound (TRUS) \< 50cc
* ECOG performance status 0-1

Exclusion Criteria:

* Any of the following prior therapies: transurethral resection of the prostate (TURP), radionuclide (permanent or temporary implantation) prostate brachytherapy, prostatectomy or prostatic cryosurgery, HIFU (high-intensity focused ultrasound), bilateral orchiectomy, chemotherapy for prostatic carcinoma
* Evidence of castrate resistance (defined as PSA \> 3 ng/mL while testosterone is \< 1.7 nmol/L). Patients could have been on combined androgen blockade with initial radiotherapy but are excluded if this was started due to PSA progression.

• DERIVEDPaulin G, Morton G, Loblaw A, Tseng CL, Corkum M, Murgic J, Ravi A, Davidson M, Wronski M, Paudel M, Haider M, Deabreu A, Zhang L, Chung HT. Updated results of MR-assisted focal salvage HDR prostate brachytherapy: a prospective study. Radiother Oncol. 2025 Oct;211:111091. doi: 10.1016/j.radonc.2025.111091. Epub 2025 Aug 9. PMID 40789422