5500/20 vs. SABR or Brachytherapy for PRimary OligoMetastatic Prostate Cancer Treatment (PROMPT)

NCT04610372 | Recruiting DMC

• 1 other identifier: H20-01207
• Study Type: interventional
• Target: 168
• Locations: 1 country
• Sites: 4

Brief Summary

We will investigate whether ultrahypofractionation using stereotactic ablative radiotherapy (SABR) or brachytherapy is as well-tolerated as moderately hypofractionated external beam radiotherapy (EBRT) for treating the prostate in patients with oligometastatic prostate cancer. Secondary aims include assessment of progression-free survival (PFS) and overall survival (OS) as well as cost-effectiveness. We hypothesize that ultrahypofractionation will maintain favorable toxicity profiles and quality of life while achieving comparable or better efficacy, thereby providing a convenient and cost-effective alternative to moderately hypofractionated EBRT.

Conditions

Oligometastatic Prostate Cancer

Keywords

prostate adenocarcinoma; oligometastases; radiotherapy; hypofractionation; brachytherapy

Outcome Measures

Primary Outcomes (1)

• Urinary symptoms

  International Prostate Symptom score (0/35), higher worse

  Baseline to 2 years

Secondary Outcomes (9)

• Expanded Prostate Cancer Index (EPIC) urinary domain

  Baseline to 2 years

• EPIC bowel domain

  Baseline to 2 years

• EPIC sexual domain

  Baseline to 2 years

• Biochemical failure (time to increase in prostate specific antigen (ng/ml) to 50% > nadir

  Baseline to 3 years

• Distant metastatic failure

  Baseline to 3 years

Study Arms (4)

standard

ACTIVE COMPARATOR

External beam radiotherapy to deliver 5500 centiGray (cGy) in 20 fractions to the prostate over 4 weeks

Radiation: Hypofractionated external beam radiotherapy

High dose rate brachytherapy

EXPERIMENTAL

A single fraction of 19 Gray (Gy) is delivered to the prostate under anesthesia as an out patient.

Radiation: High dose rate brachytherapy

Permanent seed implant brachytherapy

EXPERIMENTAL

A single permanent implant of radioactive Iodine-125 seeds is performed under anesthesia as an out patient to deliver 125 Gy to the prostate

Radiation: Permanent seed implant

Stereotactic body radiotherapy

EXPERIMENTAL

36.25 Gy is delivered to the prostate in 5 fractions given either weekly or every second day, using a SABR technique.

Radiation: Stereotactic body radiotherapy

Interventions

Hypofractionated external beam radiotherapy RADIATION

5500 cGy/20 fractions delivered 5 days per week over 4 weeks

standard

High dose rate brachytherapy RADIATION

A single fraction of 19 Gy is delivered from an automated afterloading Iridium-192 source via interstitial catheters placed under ultrasound guidance

High dose rate brachytherapy

Permanent seed implant RADIATION

Iodine-125 radioactive seeds are implanted permanently in the prostate in a single procedure under transrectal ultrasound guidance

Also known as: Low dose rate brachytherapy

Permanent seed implant brachytherapy

Stereotactic body radiotherapy RADIATION

External radiation using SABR technology delivers 36.25 Gy to the prostate in 5 fractions given either once weekly for 5 weeks or every second day over 2 weeks.

Also known as: SABR

Stereotactic body radiotherapy

Eligibility Criteria

• Age: 18 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Signed study specific informed consent
• European Cooperative Oncology Group performance status 0 to 2
• Histologically confirmed adenocarcinoma of the prostate
• Any Tumor stage, any T, any N, M1
• No prior therapy for prostate cancer apart from androgen deprivation
• Planned for long-term androgen deprivation therapy (greater than 9 months in duration)
• Patient is able and willing to complete the quality of life questionnaires, and other assessments that are a part of this study
• For brachytherapy arms, patient must be technically suitable for brachytherapy according to investigator, in terms of bladder function and prostate size.

You may not qualify if:

• High metastatic burden defined as 5 or more bone metastases or visceral metastases
• Contraindications to EBRT such as active inflammatory bowel disease or previous pelvic radiation
• For Brachytherapy Arms =: Any prior Transurethral resection of prostate

Sponsors & Collaborators

• British Columbia Cancer Agency: lead

Study Sites (4)

British Columbia Cancer Agency Center for the Southern Interior

Kelowna, British Columbia, V1Y5L3, Canada

RECRUITING

Fraser Valley Cancer Center

Surrey, British Columbia, Canada

NOT YET RECRUITING

Vancouver Cancer Center

Vancouver, British Columbia, Canada

RECRUITING

Vancouver Island Cancer Center

Victoria, British Columbia, Canada

RECRUITING

MeSH Terms

Interventions

Radiosurgery

Intervention Hierarchy (Ancestors)

Radiotherapy; Therapeutics; Stereotaxic Techniques; Neurosurgical Procedures; Surgical Procedures, Operative; Investigative Techniques

Study Officials

• Juanita Crook, MD

  BCCancer

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Juanita Crook, MD

CONTACT

250 712 3958; jcrook@bccancer.bc.ca

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Radiation Oncology

Model Details: There is one standard arm (5500/20) and 3 alternative arms. The alternative arms are selected at the treating center. Thus, each randomization is 2-way, but with a 3:1 weighting so that the 4 treatment arms have equal numbers of patients.

Study Record Dates

• First Submitted: October 14, 2020
• First Posted: October 30, 2020
• Study Start: July 12, 2021
• Primary Completion (Estimated): June 30, 2030
• Study Completion (Estimated): June 30, 2033
• Last Updated: May 6, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

CA (4)