Endometrial CancerMASTECNCT07514325
MR-guided Adaptive Stereotactic Radiotherapy for Endometrial Cancer
A study testing MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week in people with Endometrial Cancer and Radiotherapy, Adjuvant, run by Radboud University Medical Center.
Trial summary
Rationale: External beam radiotherapy (EBRT) is an important cornerstone in treatment to reduce locoregional relapse in high(-intermediate) risk endometrial cancer (EC) patients. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Endometrial Cancer, Radiotherapy, Adjuvant
- What is being tested?
- MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 61 participants
- Where
- No sites listed yet
- Study dates
- 1 May 2026to 1 Mar 2033
- 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
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- In order to be eligible to participate in this study, a participant must meet all of the following criteria:
- Women aged 18 years or older with histologically proven carcinoma of the endometrium, treated with curative hysterectomy with or without bilateral salpingo-oophorectomy. All histologies may be included (endometrioid, clear cell carcinoma, de-/undifferentiated carcinoma, carcinosarcoma, other non-endometrioid)
- Candidate for adjuvant EBRT as decided by multidisciplinary tumour board, amongst others:
- FIGO IB grade 3 endometrioid carcinoma
- FIGO stage II endometrioid carcinoma
- FIGO stage IIIA-C1 endometrioid carcinoma
Show all 11Show fewer
- FIGO IB-II clear cell carcinoma
- FIGO IA-III carcinosarcioma
- Patients receiving adjuvant systemic therapy are eligible when these therapies will not be administered concurrently
- Patients receiving vaginal vault brachytherapy are eligible
- Capable of giving informed consent
Who cannot join
- A potential participant who meets any of the following criteria will be excluded from participation in this study:
- Contra-indications for MRI according to the guidelines of the local department of Radiology, inability to lay on a treatment table for 45-60 minutes or severe claustrofobia
- Presence of para-aortic lymph node metastases (FIGO stage IIIC2)
- Prior pelvic radiotherapy
- WHO performance score > 2
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: MR-guided Adaptive Stereotactic Radiotherapy for Endometrial Cancer (MASTEC)
Rationale: External beam radiotherapy (EBRT) is an important cornerstone in treatment to reduce locoregional relapse in high(-intermediate) risk endometrial cancer (EC) patients. MR-guided adaptive radiotherapy (MGART) allows for more accurate delivery of radiation beams to the patients by visualizing and correcting for interfraction motion, with subsequent reduction of safety margins around the radiotherapy plan. Objective: The MASTEC study will investigate the safety of hypofractionated MR-guided adaptive radiotherapy in five fractions for elective pelvic nodal and vaginal vault irradiation in endometrial cancer.
Study design: Phase II multicentre intervention study Study population: Patients with endometrial cancer that receive adjuvant EBRT to the pelvic nodal areas and vaginal vault (with or without vaginal brachytherapy).
Read more
Intervention (if applicable): MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week .
Main study parameters/endpoints: The primary endpoint is acute gastrointestinal and genitourinary toxicity, scored by the Common Terminology Criteria Adverse Events version 6.0. Secondary endpoints are late gastrointestinal and genitourinary toxicity, quality of life and disease free survival; disease-specific survival; overall survival and metastasis-free survival.
- Conditions
- Endometrial Cancer, Radiotherapy, Adjuvant
- Being tested
- MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week
- Keywords
- endometrial cancer, MR-guided radiotherapy, hypofractionation
- Medical subject headings
- Endometrial Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a weekRadiation
Patients will be treated with hypofractionated MR-guided adaptive radiotherapy up to 30Gy to the vaginal vault and pelvic nodal areas, contoured on T2W MRI and CT (slice thickness 3mm). Radiotherapy will not be performed on consecutive days. Radiotherapy will be performed by IMRT (7MV) on an MR-linac (Elekta Unity).
| Study group | Role | What they receive |
|---|---|---|
| Interventional arm | Experimental | MR-guided stereotactic adaptive radiotherapy Receives: Radiation: MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week |
What is being measured
The primary outcome is the main question the study is designed to answer.
Acute gastrointestinal and genitourinary toxicity (within 3 months after start of treatment)
- Primary outcomes: Acute gastrointestinal toxicity: Maximum CTCAE v6.0 grade of GI toxicity within 90 days after treatment. Acute genitourinary toxicity: Maximum CTCAE v6.0 grade of GU toxicity within 90 days after treatment.
- Secondary Outcomes Late gastrointestinal toxicity: Maximum CTCAE v6.0 grade between 90 days and 5 years after treatment.
Late genitourinary toxicity: Maximum CTCAE v6.0 grade between 90 days and 5 years after treatment.
Acute vaginal toxicity: Maximum CTCAE v6.0 grade within 90 days after treatment.
Late vaginal toxicity: Maximum CTCAE v6.0 grade between 90 days and 5 years after treatment.
Quality of life: EORTC QLQ-C30 and QLQ-EN24 scores at 6 months and annually up to 5 years.
Locoregional disease-free survival: Time to locoregional recurrence or death. Distant disease-free survival: Time to distant metastasis or death. Overall survival: Time to death from any cause. Endometrial cancer-specific survival: Time to death due to endometrial cancer
Measured: 5 years after end of treatment
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted7 Apr 2026
- Study start1 May 2026 (estimated)
- Primary completion1 Jun 2028 (estimated)
- Study completion1 Mar 2033 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Endometrial CancerStudies of the same condition, open and under way.
- More trials run by Radboud University Medical CenterThe 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
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 61 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Radboud University Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07514325
- Sponsor's protocol ID
- NL-011073
- Other IDs
- NL-011073
- Acronym
- MASTEC
- Status last verified
- Nov 2025
- First submitted
- 18 Mar 2026
- Last updated
- 7 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 7 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- MR-guided Adaptive Stereotactic Radiotherapy for Endometrial Cancer (MASTEC)
- ClinicalTrials.gov ID
- NCT07514325
- Acronym / sponsor ID
- MASTEC / NL-011073
- Conditions
- Endometrial Cancer, Radiotherapy, Adjuvant
- Keywords
- endometrial cancer, MR-guided radiotherapy, hypofractionation
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 61 participants (estimated)
- Lead sponsor
- Radboud University Medical CenterUniversity, hospital or other
- Study start
- 1 May 2026 (estimated)
- Primary completion
- 1 Jun 2028 (estimated)
- Study completion
- 1 Mar 2033 (estimated)
- First posted
- 7 Apr 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.
Rationale: External beam radiotherapy (EBRT) is an important cornerstone in treatment to reduce locoregional relapse in high(-intermediate) risk endometrial cancer (EC) patients. MR-guided adaptive radiotherapy (MGART) allows for more accurate delivery of radiation beams to the patients by visualizing and correcting for interfraction motion, with subsequent reduction of safety margins around the radiotherapy plan. Objective: The MASTEC study will investigate the safety of hypofractionated MR-guided adaptive radiotherapy in five fractions for elective pelvic nodal and vaginal vault irradiation in endometrial cancer.
Study design: Phase II multicentre intervention study Study population: Patients with endometrial cancer that receive adjuvant EBRT to the pelvic nodal areas and vaginal vault (with or without vaginal brachytherapy).
Intervention (if applicable): MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week .
Main study parameters/endpoints: The primary endpoint is acute gastrointestinal and genitourinary toxicity, scored by the Common Terminology Criteria Adverse Events version 6.0. Secondary endpoints are late gastrointestinal and genitourinary toxicity, quality of life and disease free survival; disease-specific survival; overall survival and metastasis-free survival.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Interventional arm | Experimental | Radiation: MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a weekMR-guided stereotactic adaptive radiotherapy |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- In order to be eligible to participate in this study, a participant must meet all of the following criteria:
- Women aged 18 years or older with histologically proven carcinoma of the endometrium, treated with curative hysterectomy with or without bilateral salpingo-oophorectomy. All histologies may be included (endometrioid, clear cell carcinoma, de-/undifferentiated carcinoma, carcinosarcoma, other non-endometrioid)
- Candidate for adjuvant EBRT as decided by multidisciplinary tumour board, amongst others:
- Patients receiving adjuvant systemic therapy are eligible when these therapies will not be administered concurrently
- Patients receiving vaginal vault brachytherapy are eligible
Key exclusion criteria (5 listed)
- A potential participant who meets any of the following criteria will be excluded from participation in this study:
- Contra-indications for MRI according to the guidelines of the local department of Radiology, inability to lay on a treatment table for 45-60 minutes or severe claustrofobia
- Presence of para-aortic lymph node metastases (FIGO stage IIIC2)
- Prior pelvic radiotherapy
- WHO performance score > 2
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 |
|---|---|---|
| MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a weekPatients will be treated with hypofractionated MR-guided adaptive radiotherapy up to 30Gy to the vaginal vault and pelvic nodal areas, contoured on T2W MRI and CT (slice thickness 3mm). Radiotherapy will not be performed on consecutive days. Radiotherapy will be performed by IMRT (7MV) on an MR-linac (Elekta Unity). | Radiation | Interventional arm |
Primary outcome
Acute gastrointestinal and genitourinary toxicity (within 3 months after start of treatment)
Time frame: 5 years after end of treatment
1. Primary outcomes: Acute gastrointestinal toxicity: Maximum CTCAE v6.0 grade of GI toxicity within 90 days after treatment. Acute genitourinary toxicity: Maximum CTCAE v6.0 grade of GU toxicity within 90 days after treatment. 2. Secondary Outcomes Late gastrointestinal toxicity: Maximum CTCAE v6.0 grade between 90 days and 5 years after treatment. Late genitourinary toxicity: Maximum CTCAE v6.0 grade between 90 days and 5 years after treatment. Acute vaginal toxicity: Maximum CTCAE v6.0 grade within 90 days after treatment. Late vaginal toxicity: Maximum CTCAE v6.0 grade between 90 days and 5 years after treatment. Quality of life: EORTC QLQ-C30 and QLQ-EN24 scores at 6 months and annually up to 5 years. Locoregional disease-free survival: Time to locoregional recurrence or death. Distant disease-free survival: Time to distant metastasis or death. Overall survival: Time to death from any cause. Endometrial cancer-specific survival: Time to death due to endometrial cancer
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 7 Apr 2026.
- Individual participant dataSharing planned: Undecided
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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.
Questions about this trial
What is this clinical trial studying?
A study testing MR-guided adaptive radiotherapy (MGART) with reduced PTV margins, including 5 times 6Gy to the vaginal vault and pelvic nodal areas, 2 times a week in people with Endometrial Cancer and Radiotherapy, Adjuvant, run by Radboud University Medical Center.
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 11 inclusion and 5 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 7 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
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 Casper Reijnen, MD, PhD (0031243614505, casper.reijnen@radboudumc.nl), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Acute gastrointestinal and genitourinary toxicity (within 3 months after start of treatment) (time frame: 5 years after end of treatment). 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 7 Apr 2026.