Comparing proton and photon therapy for high-risk prostate cancer

Lymph Node Radiation Therapy with Integrated Boost to Prostate for High-risk Prostate Cancer a Randomized Phase 3 Trial Comparing Photons Vs. Protons

Not applicable Interventional University of Aarhus · NCT05350475

This study is testing whether proton therapy causes fewer stomach and bowel problems than photon therapy for people with high-risk prostate cancer.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment400 (estimated)
Ages18 Years and up
SexMale
SponsorUniversity of Aarhus Academic / other
Drugs / interventionsradiation
Locations7 sites (Copenhagen, Capital Region and 6 other locations)
Trial IDNCT05350475 on ClinicalTrials.gov

What this trial studies

This study aims to compare the late gastro-intestinal side effects of proton therapy versus photon therapy in patients with high-risk prostate cancer undergoing whole pelvic irradiation. It is a national open-label phase III randomized controlled trial that includes patients with localized or locally advanced prostate cancer and elective lymph node irradiation. The primary goal is to determine if proton therapy can reduce significant gastro-intestinal toxicity compared to photon therapy, measured by the Expanded Prostate Cancer Index Composite-26 bowel scores at 24 months. Secondary endpoints will assess morbidity, quality of life, and survival data over a period of up to 10 years.

Who should consider this trial

Good fit: Ideal candidates are men aged 18 and older with histologically verified localized or locally advanced prostate cancer who require elective lymph node irradiation.

Not a fit: Patients with previous treatments for prostate cancer or those with certain pelvic metal devices may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to reduced side effects and improved quality of life for patients with high-risk prostate cancer.

How similar studies have performed: Previous studies have shown promising results with proton therapy in reducing side effects in various cancers, suggesting potential success for this approach in prostate cancer.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histologically verified localized/locally advanced prostate cancer T1-3bN0-1M0 (TNM 8th edition). A clinical T4 is allowed if it is because of invasion into the bladder neck.
* Adenocarcinoma (mixed histology allowed as long as the adenocarcinoma component comprise more than 50%)
* Indication for elective lymph node irradiation
* PSA \< 100 ng/mL
* Age ≥18 years
* Performance status 0-1
* Life expectancy ≥ 10 years
* Able to understand and comply with the treatment protocol
* No evidence of inflammatory bowel disease Ability to adhere to procedures for study and follow-up
* Signed informed consent to participate in the study

Exclusion Criteria:

* No previous treatment for prostate cancer
* Hip-prostheses
* Other metal devices in the pelvic region (except fiducials)
* Previous major abdominal/rectal surgery
* Any other malignancy the last five years except for basal or squamous cell skin cancer
* Unable to understand patient information or comply with treatment and safety instructions
* Unable to read and understand patient information due to cognitive disabilities or language (Danish).

Where this trial is running

Copenhagen, Capital Region and 6 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Prostate CancerRadiotherapy Side EffectProton TherapyHigh RiskIntensity Modulated Radiotherapy
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.