RecruitingInterventional

Two-fraction High Dose Rate Brachytherapy as Monotherapy Delivered Three Hours Apart in Localized Prostate Cancer: A Pilot Study

NCT ID: NCT05665738Sponsor: University of California, San FranciscoLast updated: 2026-06-05

Summary

This is a single center single arm prospective pilot study investigating the safety of high dose rate (HDR) brachytherapy as monotherapy delivered in 2 fractions 3 hours apart. HDR monotherapy has been established as safe and effective in this context, however previous studies have delivered 2 fractions on separate days, or at least 6 hours apart. Clinically, this regimen, if shown to be safe and effective in future studies, has the potential to reduce operative resources and logistical stresses on brachytherapy departments.

Detailed description

PRIMARY OBJECTIVES: I. To determine the safety of HDR monotherapy 13.5 Gy x 2 fractions delivered 3 hours apart in patients with low and intermediate risk prostate cancer. SECONDARY OBJECTIVES: I. To describe the prostate specific antigen (PSA) kinetics associated with HDR brachytherapy monotherapy 13.5 Gy x 2 fractions delivered 3 hours apart for low and intermediate risk prostate cancer. OUTLINE: Treatment will be administered on an outpatient basis. All treatment will be delivered over a single day. Participants will be followed for 6 months after last treatment or removal from study, or until death, whichever occurs first. Additional Follow up will be as per usual guidelines for prostate cancer, every 3 months following treatment with PSA for the first year, then every 4 months after year 2, and every 6 months after year 3 until 5 years of follow up are completed.

Arms & interventions

RadiationHigh Dose Rate Monotherapy
High dose rate brachytherapy delivered in 13.5 Gy x 2 fractions over a single implant procedure 3 hours apart

Outcome measures

Primary

Proportion of participants with treatment-related adverse events
The proportion of participants with reported grade 3 or higher genitourinary (GU) or gastrointestinal (GI) toxicities, as graded by the NCI Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 will be reported.
Time frame: Up to 6 months

Secondary

Mean Prostate Specific Antigen (PSA) Nadir
Time frame: Up to 6 months
Mean Time to PSA Nadir
Time frame: Up to 6 months
Mean Change in International Prostate Symptom Score (IPSS) over time
Time frame: Up to 6 months

Eligibility criteria

Sex: MaleAge: 18 Years and olderHealthy volunteers: No

Inclusion Criteria: 1. Participants must have histologically or cytologically confirmed diagnosis of prostate adenocarcinoma. 2. National Comprehensive Cancer Network low to intermediate risk stratification. 3. No prior treatment for prostate cancer and no prior androgen deprivation therapy. 4. Age \>=18 years. 5. Eastern Cooperative Oncology Group (ECOG) performance status \<2 (Karnofsky \>60%. 6. Eligible to undergo High dose rate (HDR) brachytherapy as monotherapy as determined by the treating radiation oncologist. 7. Ability to understand and the willingness to sign a written informed consent document. 8. Human immunodeficiency virus (HIV)-infected individuals on effective anti-retroviral therapy with undetectable viral load within 6 months are eligible for this trial. 9. For participants with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated. 10. Individuals with a history of hepatitis C virus (HCV) infection must have been treated and cured. For individuals with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load. 11. Individuals with a prior or concurrent malignancy whose natural history or treatment does not have the potential to interfere with the safety or efficacy assessment of the investigational regimen are eligible for this trial. Exclusion Criteria: 1. Any prior treatment for prostate cancer. 2. Any prior androgen deprivation therapy. 3. Is currently receiving any other investigational agents. 4. Abnormal pre-brachytherapy assessment raising concern for undergoing HDR brachytherapy procedure. 5. Contraindications to general anesthesia. 6. Contraindications to radiotherapy. 7. Prior cryosurgery or cryotherapy to the prostate. 8. Prior transurethral resection of the prostate within the previous 6 months.

Study locations (1)

University of California, San Francisco

San Francisco, California, 94143

Recruiting

Imani Dunn · Contact

877-827-3222 Imani.Dunn@ucsf.edu

· Contact

877-827-3222 cancertrials@ucsf.edu

I-Chow Hsu, MD · Principal Investigator

References

Martell K, Mendez LC, Chung HT, Tseng CL, Alayed Y, Cheung P, Liu S, Vesprini D, Chu W, Wronski M, Szumacher E, Ravi A, Loblaw A, Morton G. Results of 15 Gy HDR-BT boost plus EBRT in intermediate-risk prostate cancer: Analysis of over 500 patients. Radiother Oncol. 2019 Dec;141:149-155. doi: 10.1016/j.radonc.2019.08.017. Epub 2019 Sep 12.(PubMed)
Viani GA, Arruda CV, Assis Pellizzon AC, De Fendi LI. HDR brachytherapy as monotherapy for prostate cancer: A systematic review with meta-analysis. Brachytherapy. 2021 Mar-Apr;20(2):307-314. doi: 10.1016/j.brachy.2020.10.009. Epub 2021 Jan 15.(PubMed)
Morton G, McGuffin M, Chung HT, Tseng CL, Helou J, Ravi A, Cheung P, Szumacher E, Liu S, Chu W, Zhang L, Mamedov A, Loblaw A. Prostate high dose-rate brachytherapy as monotherapy for low and intermediate risk prostate cancer: Efficacy results from a randomized phase II clinical trial of one fraction of 19 Gy or two fractions of 13.5 Gy. Radiother Oncol. 2020 May;146:90-96. doi: 10.1016/j.radonc.2020.02.009. Epub 2020 Mar 5.(PubMed)
Alayed Y, Loblaw A, McGuffin M, Chung HT, Tseng CL, D'Alimonte L, Cheung P, Liu S, Chu W, Szumacher E, Helou J, Ravi A, Haider M, Mamedov A, Zhang L, Morton G. Single-fraction HDR brachytherapy as monotherapy in low and intermediate risk prostate cancer: Outcomes from two clinical trials with and without an MRI-guided boost. Radiother Oncol. 2021 Jan;154:29-35. doi: 10.1016/j.radonc.2020.09.007. Epub 2020 Sep 10.(PubMed)
Corkum MT, Achard V, Morton G, Zilli T. Ultrahypofractionated Radiotherapy for Localised Prostate Cancer: How Far Can We Go? Clin Oncol (R Coll Radiol). 2022 May;34(5):340-349. doi: 10.1016/j.clon.2021.12.006. Epub 2021 Dec 25.(PubMed)
Kukielka AM, Dabrowski T, Walasek T, Olchawa A, Kudzia R, Dybek D. High-dose-rate brachytherapy as a monotherapy for prostate cancer--Single-institution results of the extreme fractionation regimen. Brachytherapy. 2015 May-Jun;14(3):359-65. doi: 10.1016/j.brachy.2015.01.004. Epub 2015 Feb 28.(PubMed)