Clinical trial · Interventional
PRO-BOOST-LC: Whole-Gland Boost Strategies Versus SBRT Monotherapy in PSMA-Staged Localized and Locally Advanced Prostate Cancer
PRO-BOOST-LC: A Prospective, Multi-arm Phase II/III Clinical Trial Evaluating the Efficacy and Safety of Whole-Gland Boost Using HDR Brachytherapy, LDR Brachytherapy, or Single-Fraction SBRT Following an Ultrahypofractionated EBRT (VMAT) Backbone (5 Gy x 5 Fractions) Compared to Standard SBRT Monotherapy in Patients With Localized and Locally Advanced Prostate Cancer Staged With PSMA PET/CT
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
PRO-BOOST-LC is a prospective, multicenter, randomized phase II/III clinical trial for men with localized or locally advanced prostate cancer without lymph node or distant metastases, confirmed using prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT). Radiotherapy is an established curative treatment option for prostate cancer. Several modern radiotherapy strategies can safely deliver high radiation doses to the prostate while limiting dose to surrounding organs. These include stereotactic body radiotherapy (SBRT), high-dose-rate (HDR) brachytherapy, low-dose-rate (LDR) brachytherapy, and combinations of external beam radiotherapy with a prostate boost. However, the optimal dose-escalation strategy for balancing cancer control, treatment-related toxicity, and long-term quality of life remains uncertain in patients staged with modern PSMA PET imaging. The aim of PRO-BOOST-LC is to compare definitive SBRT monotherapy with whole-gland prostate boost strategies delivered after a short course of external beam radiotherapy. Participants will be randomly assigned, according to center capability and patient-level technical suitability, to one of the protocol-defined treatment options. The control group receives SBRT monotherapy. The experimental groups receive external beam radiotherapy followed by one of three whole-gland boost techniques: HDR brachytherapy, LDR brachytherapy, or single-fraction SBRT boost. The primary objective is to determine whether assignment to a prostate boost strategy improves failure-free survival compared with SBRT monotherapy. Failure-free survival includes biochemical recurrence, local or regional progression, distant metastases, progression-driven salvage treatment, or death from any cause. Key secondary outcomes include metastasis-free survival, overall survival, physician-reported treatment-related toxicity, and patient-reported quality of life, including urinary, bowel, and sexual function. Participants will undergo baseline clinical evaluation, PSA testing, prostate MRI, PSMA PET/CT, and quality-of-life assessments. After treatment, participants will be followed regularly with clinical assessments, PSA testing, toxicity evaluation, patient questionnaires, and imaging when clinically indicated. The study is designed to provide long-term evidence on how best to use modern radiotherapy dose escalation for patients with PSMA-staged localized or locally advanced prostate cancer.
Conditions
Conditions (5)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Dose Escalation: Solid Tumors | — | UNRESOLVED | — |
| Localized Prostate Cancer | Malignant Prostate Neoplasm | CURATED_BROADER | 0.78 |
| Prostate Brachytherapy | — | UNRESOLVED | — |
| Prostate Cancer (Adenocarcinoma) | Malignant Prostate Neoplasm | CURATED_EXACT | 0.85 |
| Stereotactic Body Radiation Therapy (SBRT) | — | UNRESOLVED | — |
Interventions
Interventions (6)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Androgen Deprivation Therapy (ADT) | Drug | — | UNRESOLVED |
| External Beam Radiotherapy (EBRT) Backbone | Radiation | — | UNRESOLVED |
| High-Dose-Rate Brachytherapy Boost | Radiation | — | UNRESOLVED |
| Low-Dose-Rate Brachytherapy Boost | Radiation | — | UNRESOLVED |
| Stereotactic Body Radiotherapy (SBRT) Boost | Radiation | — | UNRESOLVED |
| Stereotactic Body Radiotherapy (SBRT) Monotherapy | Radiation | — | UNRESOLVED |
Design
Arms and outcomes
Arms (4)
- type
- ACTIVE_COMPARATOR
- label
- SBRT Monotherapy
- description
- Patients assigned to this arm receive definitive stereotactic body radiotherapy (SBRT) delivered to the prostate as monotherapy, without any additional intraprostatic boost. Treatment is administered using an ultrahypofractionated regimen with highly conformal dose delivery, daily image guidance, and motion management according to protocol-defined standards. Target volumes and organs at risk are contoured following centralized guidelines, and treatment planning adheres to predefined coverage objectives and dose constraints. This arm represents a contemporary, non-invasive definitive radiotherapy strategy for localized prostate cancer and serves as the active comparator for all boost-based dose escalation approaches evaluated in the study. Androgen deprivation therapy may be administered according to protocol-defined risk group and current clinical practice guidelines.
- interventionNames
- Radiation: Stereotactic Body Radiotherapy (SBRT) Monotherapy
- Drug: Androgen Deprivation Therapy (ADT)
- type
- EXPERIMENTAL
- label
- EBRT With HDR Brachytherapy Boost
- description
- Patients assigned to this arm receive a standardized ultrahypofractionated external beam radiotherapy (EBRT) backbone delivered to the prostate using modern image-guided techniques, followed by an intraprostatic boost delivered with high-dose-rate (HDR) brachytherapy. The EBRT component provides uniform baseline irradiation, after which a single-fraction HDR brachytherapy boost is administered using transperineal catheter placement and afterloading according to protocol-defined technical and dosimetric criteria. This approach enables delivery of a very high biologically effective dose to the prostate while maintaining strict organ-at-risk constraints. Target coverage objectives, applicator placement principles, and dose limits are standardized across centers. Androgen deprivation therapy may be administered according to protocol-defined risk group and standard clinical practice.
Eligibility
Eligibility (as posted)
- Sex
- Male
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: * Male patients aged ≥18 years. * Histologically confirmed adenocarcinoma of the prostate. * Localized or locally advanced prostate cancer classified as cT1-4, cN0, cM0. * Negative pelvic nodal and distant metastatic disease on baseline PSMA PET. * NCCN favourbale or unfavourbale intermediate-, high-, or very high-risk disease. * Candidate for definitive radiotherapy with curative intent. * ECOG performance status 0-2. * Baseline PSA available prior to randomization. * Ability to undergo external beam radiotherapy and brachytherapy or SBRT according to protocol. * Planned androgen deprivation therapy (ADT) permitted according to protocol-defined risk group. * Ability to understand and willingness to sign written informed consent. Exclusion Criteria: * Evidence of pelvic nodal (cN1) or distant metastatic disease (cM1) on baseline imaging. * Prior definitive local treatment for prostate cancer, including prostatectomy, brachytherapy, or definitive external beam radiotherapy. * Prior pelvic radiotherapy for any malignancy. * Prior systemic therapy for prostate cancer other than protocol-allowed neoadjuvant ADT. * History of other active malignancy requiring systemic treatment (except adequately treated non-melanoma skin cancer). * Contraindications to radiotherapy or anesthesia required for brachytherapy procedures. * Severe uncontrolled comorbidities that would preclude protocol treatment. * Inability to comply with study procedures or follow-up schedule.
References
Publications (17)
- BACKGROUNDNational Comprehensive Cancer Network (NCCN). NCCN Clinical Practice Guidelines in Oncology: Prostate Cancer. Version current at study initiation. Available at: https://www.nccn.org/professionals/physician_gls/pdf/prostate.pdf
- BACKGROUNDSidibe I, Beaudry MM, Carignan D, Froment MA, Foster W, Bachand F, Vigneault E, Magnan S, Aubin S, Morrier J, Poulin E, Lacroix F, Lavallee MC, Beaulieu L, Martin AG. Ultra-hypofractionated radiotherapy combined with HDR brachytherapy: An optimized treatment. Radiother Oncol. 2026 Jan;214:111199. doi: 10.1016/j.radonc.2025.111199. Epub 2025 Oct 9. PMID 41067642
- BACKGROUNDMendez LC, Crook J, Martell K, Schaly B, Hoover DA, Dhar A, Velker V, Ahmad B, Lock M, Halperin R, Warner A, Bauman GS, D'Souza DP. Is Ultrahypofractionated Whole Pelvis Radiation Therapy (WPRT) as Well Tolerated as Conventionally Fractionated WPRT in Patients With Prostate Cancer? Early Results From the HOPE Trial. Int J Radiat Oncol Biol Phys. 2024 Jul 1;119(3):803-812. doi: 10.1016/j.ijrobp.2023.11.058. Epub 2023 Dec 8. PMID 38072323
- BACKGROUNDBeaudry MM, Carignan D, Foster W, Lavallee MC, Aubin S, Lacroix F, Poulin E, Lachance B, Despres P, Beaulieu L, Vigneault E, Martin AG. Comparison of four-year toxicities and local control of ultra-hypofractionated vs moderate-hypofractionated image guided prostate radiation with HDR brachytherapy boost: A phase I-II single institution trial. Clin Transl Radiat Oncol. 2023 Feb 8;40:100593. doi: 10.1016/j.ctro.2023.100593. eCollection 2023 May. PMID 36875870
- BACKGROUNDGorovets D, Hopkins M, Kollmeier M, Moore A, Goel A, Shasha D, Brennan V, McBride S, Cohen G, Damato AL, Zelefsky MJ. Early outcomes of high-dose-rate brachytherapy combined with ultra-hypofractionated radiation in higher-risk prostate cancer. Brachytherapy. 2021 Nov-Dec;20(6):1099-1106. doi: 10.1016/j.brachy.2021.08.006. Epub 2021 Sep 26. PMID 34588146
- BACKGROUNDKollmeier MA, Gorovets D, Flynn J, McBride S, Brennan V, Beaudry J, Cohen G, Damato A, Zhang Z, Zelefsky MJ. Combined brachytherapy and ultra-hypofractionated radiotherapy for intermediate-risk prostate cancer: Comparison of toxicity outcomes using a high-dose-rate (HDR) versus low-dose-rate (LDR) brachytherapy boost. Brachytherapy. 2022 Sep-Oct;21(5):599-604. doi: 10.1016/j.brachy.2022.04.006. Epub 2022 Jun 17.