Adaptive Stereotactic Radiotherapy for Localized Prostate Cancer

NCT07344844 | Recruiting

• 1 other identifier: 2025-A00339-40
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

This study evaluates whether adaptive stereotactic body radiotherapy (SBRT) provides dosimetric advantages compared to non-adaptive SBRT in localized prostate cancer. Five low-dose CT scans are performed before each SBRT session to assess anatomical variations (bladder filling, rectal volume) and determine if a dosimetric recalculation would have been required. The study also evaluates cumulative dose to organs at risk, patient-reported quality of life over 24 months, and overall and recurrence-free survival.

Conditions

Prostate Cancer (Adenocarcinoma)

Keywords

SBRT; Cyberknife; radiotherapy

Outcome Measures

Primary Outcomes (1)

• Proportion of patients requiring dosimetric recalculation due to anatomical variations

  Percentage of patients for whom at least one stereotactic body radiotherapy (SBRT) fraction would have required a dosimetric recalculation due to anatomical variations (bladder filling and/or rectal emptying), based on comparison between the initial treatment plan and pre-treatment low-dose CT scans acquired before each SBRT fraction (5). This outcome reflects the potential benefit of an adaptive radiotherapy approach compared to a non-adaptive strategy.

  At each of the 5 SBRT sessions (10 days max) Based on scanners low-dose comparison.

Secondary Outcomes (6)

• Cumulative delivered dose to Organs at Risk (OARs)

  From baseline CT + all 5 fraction low-dose CT scans. (up to 10 days)

• Change from baseline in global quality of life (EORTC QLQ-C30)

  Time Frame: Baseline (pre-radiotherapy) 1 month 3 months 6 months 12 months 18 months 24 months post-radiotherapy

• Survival outcomes

  1, 3, 6, 12, 18, 24 months post-radiotherapy

• Recurrence-Free Survival (RFS)

  1, 3, 6, 12, 18, 24 months post-radiotherapy

• Change from baseline in prostate cancer-specific quality of life (EORTC QLQ-PR25)

  Baseline, 1, 3, 6, 12, 18, and 24 months post-radiotherapy

Study Arms (1)

Patients treated by SBRT with pre-session low-dose CT

OTHER

Five low-dose, non-contrast CT scans performed immediately before each SBRT session (≈10 min before treatment) to assess anatomical variations impacting target volume and organ-at-risk dosimetry.

Other: Low-dose CT imaging before each SBRT session

Interventions

Low-dose CT imaging before each SBRT session OTHER

Five low-dose, non-contrast CT scans performed immediately before each SBRT session (≈10 min before treatment) to assess anatomical variations impacting target volume and organ-at-risk dosimetry.

Patients treated by SBRT with pre-session low-dose CT

Eligibility Criteria

• Age: 60 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male aged ≥60 years
• Localized prostate cancer of low or intermediate risk (T1-T2)
• Gleason score 6-7
• PSA \<15 ng/mL
• No evidence of metastatic disease
• Radiotherapy indicated for prostate cancer
• Affiliated with or benefiting from a French social security system
• French-speaking patient
• Patient appropriately informed and having signed a written informed consent form

You may not qualify if:

• Unable to read, write, or understand French
• Vulnerable patient as defined by Article L1121-6 of the French Public Health Code
• Adult under guardianship, curatorship, or legal protection ("sauvegarde de justice")
• Patient unable to personally provide informed consent according to Article L1121-8 of the French Public Health Code
• Patient already included in another interventional study that could interfere with study outcomes
• History of urological (prostate) or digestive surgery that could influence study outcomes
• Refusal to sign the written informed consent form

Sponsors & Collaborators

• Clinique Sainte Clotilde: lead

Study Sites (1)

Clinique Sainte Clotilde

Saint-Denis, 97404, Reunion

RECRUITING

MeSH Terms

Conditions

Prostatic Neoplasms; Adenocarcinoma

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases; Carcinoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type

Study Officials

• Youssef Slama

  Clinique Sainte Clotilde

  STUDY CHAIR

Central Study Contacts

MANON Leprince, Clinical Research Associate

CONTACT

0692341365; manon.leprince@clinifutur.net

Mickael Begue, Principal Investigator

CONTACT

manon.leprince@clinifutur.net

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 15, 2025
• First Posted: January 15, 2026
• Study Start: November 18, 2025
• Primary Completion (Estimated): March 1, 2029
• Study Completion (Estimated): May 1, 2029
• Last Updated: January 15, 2026

Record last verified: 2026-01

Locations

RE (1)