Locally Advanced Rectal CancerPROSPECT-WWNCT07903883
Dose-Escalated Short-Course Proton Therapy for Locally Advanced Rectal Cancer
A study testing Intensity modulated proton therapy in people with Locally Advanced Rectal Cancer and Rectal Adenocarcinoma, run by University of Aarhus at 8 sites in Denmark.
Trial summary
This prospective national multicentre feasibility study evaluates dose-escalated short-course proton radiotherapy followed by total neoadjuvant chemotherapy in patients with primary high-risk locally advanced rectal adenocarcinoma. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Locally Advanced Rectal Cancer, Rectal Adenocarcinoma
- What is being tested?
- Intensity modulated proton therapy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- 8 sitesDenmark
- Study dates
- Nov 2026to Nov 2034
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18 years or older.
- Eastern Cooperative Oncology Group performance status 0-1.
- Fit for combination chemotherapy.
- Biopsy-verified primary locally advanced rectal adenocarcinoma.
- At least one high-risk feature: cT3c, cT4a, or cT4b disease; tumour or lymph node 1 mm or less from the mesorectal fascia; enlarged lateral pelvic lymph nodes; or extramural vascular invasion on MRI.
- Laboratory values adequate for chemotherapy according to local guidelines.
Show all 9Show fewer
- Able to understand the study information and provide written informed consent.
- Willing to receive dose-escalated short-course proton radiotherapy.
- Willing and able to travel to the Danish Centre for Particle Therapy for planning and treatment.
Who cannot join
- Rectal tumour invading cranial sacral bone or lumbosacral nerve roots.
- Distant metastatic disease at baseline (M1).
- Mismatch repair-deficient or microsatellite instability-high tumour.
- Recurrent rectal cancer.
- Previous pelvic radiotherapy.
- Serious comorbidity or other condition making total neoadjuvant therapy unsafe in the investigator's judgement.
Show all 10Show fewer
- Pregnancy or breastfeeding.
- Inability to comply with study procedures or follow-up.
- Implant, including an artificial hip, that precludes proton therapy.
- Contraindication to MRI, including an incompatible cardiac implantable electronic device.
Trial locations and contacts
8 sites in 1 country. Contact the study team or a site near you to ask about taking part.
8 sites in 1 country
Denmark8 sites
Aalborg University Hospital
Aalborg
Danish Centre for Particle Therapy
Aarhus, 8200
Aarhus University Hospital
Aarhus
Rigshospitalet
Copenhagen
Herlev Hospital
Herlev
Zealand University Hospital, Naestved
Næstved
Odense University Hospital
Odense
Vejle Hospital
Vejle
About this study
Official title: Feasibility of Dose-Escalated Short-Course Proton Therapy for Locally Advanced Rectal Cancer: A National Multicentre Feasibility Study to Prepare a Phase III Randomised Trial
This prospective national multicentre feasibility study evaluates dose-escalated short-course proton radiotherapy followed by total neoadjuvant chemotherapy in patients with primary high-risk locally advanced rectal adenocarcinoma. The study will assess willingness to participate and travel for proton therapy, completion of planned treatment, early clinical complete response, safety, patient-reported outcomes, and feasibility of circulating cell-free and tumour DNA sampling. Patients with a clinical complete response may enter a watch-and-wait programme; other patients will undergo surgery according to national guidelines.
Read the detailed description
Standard short-course radiotherapy for locally advanced rectal cancer is 25 Gy in 5 fractions. Dose escalation may increase tumour response and the probability of organ preservation but may also increase radiation exposure of adjacent normal tissues. Proton therapy may permit dose escalation while limiting dose to organs at risk.
Participants will receive intensity-modulated proton therapy with 35 Gy(RBE) in 5 fractions to the tumour target and 25 Gy(RBE) in 5 fractions to the elective target. Radiotherapy will be followed, approximately 2 weeks later, by 4 cycles of CAPOX or FOLFOX according to national guidelines. Response will be assessed 20-22 weeks after the start of radiotherapy by multidisciplinary review of digital rectal examination, endoscopy, and pelvic MRI. Patients with a clinical complete response may be managed by watch-and-wait; surgery and subsequent follow-up will otherwise follow national guidelines.
Toxicity, patient-reported symptoms, quality of life, and oncological outcomes will be followed for up to 60 months. Blood for exploratory cfDNA/ctDNA analyses will be collected at baseline, at the end of radiotherapy, and at the 20-22-week response assessment.
- Being tested
- Intensity modulated proton therapy
- Keywords
- Proton therapy, Rectal cancer, Short-course radiotherapy, Dose escalation, Total neoadjuvant therapy, Watch and wait, Organ preservation, Circulating tumour DNA
- Medical subject headings
- Rectal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Intensity modulated proton therapyRadiation
Dose-escalated IMPT
| Study group | Role | What they receive |
|---|---|---|
| Dose-escalated proton therapy | Experimental | One-armed feasibility study where patients will be treated with dose-escalated IMPT 35Gy in 5 fractions Receives: Radiation: Intensity modulated proton therapy |
What is being measured
The primary outcome is the main question the study is designed to answer.
Feasibility of recruitment
Proportion of eligible patients who are willing to participate i trial and travel proton facility
Measured: 2 year inclusion expected
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Oct 2026
- Study startNov 2026 (estimated)
- Primary completionNov 2029 (estimated)
- Study completionNov 2034 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Locally Advanced Rectal CancerStudies of the same condition, open and under way.
- More trials run by University of AarhusThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Model description
- All enrolled participants receive dose-escalated short-course proton radiotherapy followed by chemotherapy.
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Aarhus
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Camilla Kronborg, University of Aarhus
- Investigators
- Camilla Kronborg, MD, PhD, Principal investigator, Danish Centre for Particle Therapy, Aarhus University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07903883
- Sponsor's protocol ID
- DCPT-RECTUM-PROTON-FEAS-2026
- Acronym
- PROSPECT-WW
- Status last verified
- Oct 2026
- First submitted
- 22 Oct 2026
- Last updated
- 29 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Feasibility of Dose-Escalated Short-Course Proton Therapy for Locally Advanced Rectal Cancer: A National Multicentre Feasibility Study to Prepare a Phase III Randomised Trial
- ClinicalTrials.gov ID
- NCT07903883
- Acronym / sponsor ID
- PROSPECT-WW / DCPT-RECTUM-PROTON-FEAS-2026
- Keywords
- Proton therapy, Rectal cancer, Short-course radiotherapy, Dose escalation, Total neoadjuvant therapy, Watch and wait, Organ preservation, Circulating tumour DNA
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- University of AarhusUniversity, hospital or other
- Study start
- Nov 2026 (estimated)
- Primary completion
- Nov 2029 (estimated)
- Study completion
- Nov 2034 (estimated)
- First posted
- 29 Oct 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This prospective national multicentre feasibility study evaluates dose-escalated short-course proton radiotherapy followed by total neoadjuvant chemotherapy in patients with primary high-risk locally advanced rectal adenocarcinoma. The study will assess willingness to participate and travel for proton therapy, completion of planned treatment, early clinical complete response, safety, patient-reported outcomes, and feasibility of circulating cell-free and tumour DNA sampling. Patients with a clinical complete response may enter a watch-and-wait programme; other patients will undergo surgery according to national guidelines.
Detailed description
Standard short-course radiotherapy for locally advanced rectal cancer is 25 Gy in 5 fractions. Dose escalation may increase tumour response and the probability of organ preservation but may also increase radiation exposure of adjacent normal tissues. Proton therapy may permit dose escalation while limiting dose to organs at risk.
Participants will receive intensity-modulated proton therapy with 35 Gy(RBE) in 5 fractions to the tumour target and 25 Gy(RBE) in 5 fractions to the elective target. Radiotherapy will be followed, approximately 2 weeks later, by 4 cycles of CAPOX or FOLFOX according to national guidelines. Response will be assessed 20-22 weeks after the start of radiotherapy by multidisciplinary review of digital rectal examination, endoscopy, and pelvic MRI. Patients with a clinical complete response may be managed by watch-and-wait; surgery and subsequent follow-up will otherwise follow national guidelines.
Toxicity, patient-reported symptoms, quality of life, and oncological outcomes will be followed for up to 60 months. Blood for exploratory cfDNA/ctDNA analyses will be collected at baseline, at the end of radiotherapy, and at the 20-22-week response assessment.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- All enrolled participants receive dose-escalated short-course proton radiotherapy followed by chemotherapy.
| Arm | Type | Receives |
|---|---|---|
| Dose-escalated proton therapy | Experimental | Radiation: Intensity modulated proton therapyOne-armed feasibility study where patients will be treated with dose-escalated IMPT 35Gy in 5 fractions |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (9 listed)
- Age 18 years or older.
- Eastern Cooperative Oncology Group performance status 0-1.
- Fit for combination chemotherapy.
- Biopsy-verified primary locally advanced rectal adenocarcinoma.
- At least one high-risk feature: cT3c, cT4a, or cT4b disease; tumour or lymph node 1 mm or less from the mesorectal fascia; enlarged lateral pelvic lymph nodes; or extramural vascular invasion on MRI.
Key exclusion criteria (10 listed)
- Rectal tumour invading cranial sacral bone or lumbosacral nerve roots.
- Distant metastatic disease at baseline (M1).
- Mismatch repair-deficient or microsatellite instability-high tumour.
- Recurrent rectal cancer.
- Previous pelvic radiotherapy.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Intensity modulated proton therapyDose-escalated IMPT | Radiation | Dose-escalated proton therapy |
Primary outcome
Feasibility of recruitment
Time frame: 2 year inclusion expected
Proportion of eligible patients who are willing to participate i trial and travel proton facility
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2026.
Related trials for Locally Advanced Rectal Cancer
RecruitingPhase 1
Short Course Radiation Therapy and Combination Chemotherapy for the Treatment of Stage II-III Rectal Cancer
Locally Advanced Rectal Carcinoma, Rectal Adenocarcinoma
Active, not recruitingPhase 2
Perioperative Cadonilimab (AK104) in Locally Advanced MSI-H/dMMR Gastric or Gastroesophageal Junction and Colorectal Adenocarcinoma
MSI-H/dMMR Gastric Carcinoma and Colorectal Cancer
RecruitingPhase 2
Study of Induction PD-1 Blockade in Subjects With Locally Advanced Mismatch Repair Deficient Solid Tumors
Rectal Adenocarcinoma, Clinical Stage: Stage II (T3-4, N-)
RecruitingPhase 3
A Clinical Study of Calderasib (MK-1084) With Targeted Therapy and Chemotherapy in People With Colorectal Cancer (MK-1084-012/KANDLELIT-012)
Colon Adenocarcinoma, Rectal Adenocarcinoma
RecruitingPhase 2
Gemcitabine, Cisplatin, Nab-paclitaxel (GAP) and Cemiplimab for Locally Advanced Biliary Tract Cancer (BTC)
Colon and Rectal Cancer
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Camilla Kronborg, MD, PhD principal investigator
Danish Centre for Particle Therapy, Aarhus University Hospital
8 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Intensity modulated proton therapy in people with Locally Advanced Rectal Cancer and Rectal Adenocarcinoma, run by University of Aarhus at 8 sites in Denmark.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 8 sites in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Camilla Kronborg, MD, PhD (+45 78450000, camkro@rm.dk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Feasibility of recruitment (time frame: 2 year inclusion expected). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2026.