Peritoneal CarcinomatosisPhase 2MARACASNCT07593261
MRI-Guided Adaptive Radiotherapy for Limited Peritoneal Metastases (MARACAS Trial).
A Phase 2 study testing MRI-guided stereotactic body radiotherapy in people with Peritoneal Carcinomatosis and Oligometastatic Disease, run by Fondazione Policlinico Universitario Agostino Gemelli IRCCS at 1 site in Italy.
Trial summary
This prospective phase II study evaluates the efficacy and safety of MRI-guided stereotactic body radiotherapy (MRIgSBRT) in patients with oligometastatic peritoneal carcinomatosis from gastrointestinal or gynecological tumors. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Peritoneal Carcinomatosis, Oligometastatic Disease, Peritoneal Metastases
- What is being tested?
- MRI-guided stereotactic body radiotherapy
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 34 participants
- Where
- 1 siteItaly
- Study dates
- Jul 2026to Jul 2032
- Phase
- Phase 2
- 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
- ECOG performance status 0-2
- Life expectancy ≥6 months
- Up to 5 MRI-visible peritoneal nodules
- PCI ≤20
- No prior radiotherapy in the same abdominal region within 6 months
- Signed informed consent
- History of prior CRS and/or HIPEC
Who cannot join
- Diffuse peritoneal carcinomatosis
- Psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule (those conditions should be discussed with the patient before registration in the trial)
- Significant comorbidities (such as: severe cardiac or coagulative disease, moderate or severe
- restrictive/obsiructive lung deficit, severe cognitive impairment, moderate and severe renal and hepatic impairment.
- Pregnancy or breastfeeding
- MRI contraindications (e.g., pacemaker, severe claustrophobia)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Italy1 site
Gemelli ART (Advanced Radiation Therapy)-Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Roma, 000168
Luca Boldrini, +390630155701, luca.boldrini@policlinicogemelli.it
Luca Boldrini
About this study
Official title: MARACAS: A Phase II Trial of MRI-guided Adaptive Stereotactic RAdiotherapy in oligometastatiC Patients With Peritoneal Spread.
This prospective phase II study evaluates the efficacy and safety of MRI-guided stereotactic body radiotherapy (MRIgSBRT) in patients with oligometastatic peritoneal carcinomatosis from gastrointestinal or gynecological tumors. Eligible patients with up to 5 MRI-visible peritoneal lesions and PCI ≤20 will be treated with MRIgSBRT using a hybrid MRI-linear accelerator with online adaptive planning and real-time tumor tracking.
The primary endpoint is radiologic response rate according to RECIST 1.1 criteria. Secondary endpoints include overall survival, progression-free survival, local control, chemotherapy-free survival, and treatment-related toxicity. The study aims to assess MRIgSBRT as a safe and non-invasive treatment option for selected patients with limited peritoneal metastatic disease.
Read the detailed description
Peritoneal carcinomatosis (PC) represents a frequent metastatic pattern in gastrointestinal and gynecological malignancies and is associated with poor prognosis and limited therapeutic options. Although cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) may improve outcomes in selected patients, many patients are not candidates for surgery because of recurrent disease, comorbidities, or poor performance status.
MRI-guided stereotactic body radiotherapy (MRIgSBRT) allows highly conformal radiation delivery with online adaptive planning and real-time tumor tracking, potentially improving treatment precision and sparing surrounding organs at risk in anatomically complex abdominal sites.
This prospective single-center phase II study will evaluate MRIgSBRT in patients with oligometastatic peritoneal carcinomatosis with up to 5 MRI-visible lesions and PCI ≤20. Treatment will be delivered using a hybrid MRI-linear accelerator with adaptive planning according to daily anatomical variations.
The primary endpoint is radiologic response rate according to RECIST 1.1 criteria. Secondary endpoints include overall survival, progression-free survival, local control, chemotherapy-free survival, and treatment-related toxicity assessed according to CTCAE v5.0.
- Being tested
- MRI-guided stereotactic body radiotherapy
- Keywords
- MRI-guided radiotherapy, Stereotactic body radiotherapy, Peritoneal carcinomatosis, Peritoneal metastases, Online adaptive radiotherapy
- Medical subject headings
- Peritoneal Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
MRI-guided stereotactic body radiotherapyDevice
Patients will receive MRI-guided stereotactic body radiotherapy (MRIgSBRT) delivered using a hybrid MRI-linear accelerator with online adaptive planning and real-time tumor tracking. Treatment will consist of 30-50 Gy delivered in 5 fractions according to clinical judgment, target characteristics, and organ-at-risk constraints. Daily adaptive replanning may be performed to account for anatomical changes and optimize dose delivery in patients with oligometastatic peritoneal carcinomatosis.
| Study group | Role | What they receive |
|---|---|---|
| MRI-guided SBRT | Experimental | Patients with oligometastatic peritoneal carcinomatosis will receive MRI-guided stereotactic body radiotherapy (MRIgSBRT) delivered with a hybrid MRI-linear accelerator using online adaptive planning and real-time tumor tracking. Treatment dose will range from 30 to 50 Gy in 5 fractions according to clinical judgment and organ-at-risk constraints. Receives: Device: MRI-guided stereotactic body radiotherapy |
What is being measured
The primary outcome is the main question the study is designed to answer.
Radiological Response Rate (RR)
RR: The response rate will be calculated as the proportion of patients achieving a complete or partial radiological response out of the total number of evaluable patients according to RECIST 1.1 criteria
Measured: Up to 12 months after completion of MRIgSBRT
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 May 2026
- Study startJul 2026 (estimated)
- Primary completionJul 2029 (estimated)
- Study completionJul 2032 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Peritoneal CarcinomatosisStudies of the same condition, open and under way.
- More trials run by Fondazione Policlinico Universitario Agostino Gemelli IRCCSThe 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 2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 34 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Luca Boldrini, Principal investigator, Fondazione Policlinico Universitario Agostino Gemelli IRCCS
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07593261
- Sponsor's protocol ID
- 26983
- Acronym
- MARACAS
- Status last verified
- May 2026
- First submitted
- 12 May 2026
- Last updated
- 18 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 18 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- MARACAS: A Phase II Trial of MRI-guided Adaptive Stereotactic RAdiotherapy in oligometastatiC Patients With Peritoneal Spread.
- ClinicalTrials.gov ID
- NCT07593261
- Acronym / sponsor ID
- MARACAS / 26983
- Keywords
- MRI-guided radiotherapy, Stereotactic body radiotherapy, Peritoneal carcinomatosis, Peritoneal metastases, Online adaptive radiotherapy
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 34 participants (estimated)
- Lead sponsor
- Fondazione Policlinico Universitario Agostino Gemelli IRCCSUniversity, hospital or other
- Study start
- Jul 2026 (estimated)
- Primary completion
- Jul 2029 (estimated)
- Study completion
- Jul 2032 (estimated)
- First posted
- 18 May 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 phase II study evaluates the efficacy and safety of MRI-guided stereotactic body radiotherapy (MRIgSBRT) in patients with oligometastatic peritoneal carcinomatosis from gastrointestinal or gynecological tumors. Eligible patients with up to 5 MRI-visible peritoneal lesions and PCI ≤20 will be treated with MRIgSBRT using a hybrid MRI-linear accelerator with online adaptive planning and real-time tumor tracking.
The primary endpoint is radiologic response rate according to RECIST 1.1 criteria. Secondary endpoints include overall survival, progression-free survival, local control, chemotherapy-free survival, and treatment-related toxicity. The study aims to assess MRIgSBRT as a safe and non-invasive treatment option for selected patients with limited peritoneal metastatic disease.
Detailed description
Peritoneal carcinomatosis (PC) represents a frequent metastatic pattern in gastrointestinal and gynecological malignancies and is associated with poor prognosis and limited therapeutic options. Although cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) may improve outcomes in selected patients, many patients are not candidates for surgery because of recurrent disease, comorbidities, or poor performance status.
MRI-guided stereotactic body radiotherapy (MRIgSBRT) allows highly conformal radiation delivery with online adaptive planning and real-time tumor tracking, potentially improving treatment precision and sparing surrounding organs at risk in anatomically complex abdominal sites.
This prospective single-center phase II study will evaluate MRIgSBRT in patients with oligometastatic peritoneal carcinomatosis with up to 5 MRI-visible lesions and PCI ≤20. Treatment will be delivered using a hybrid MRI-linear accelerator with adaptive planning according to daily anatomical variations.
The primary endpoint is radiologic response rate according to RECIST 1.1 criteria. Secondary endpoints include overall survival, progression-free survival, local control, chemotherapy-free survival, and treatment-related toxicity assessed according to CTCAE v5.0.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| MRI-guided SBRT | Experimental | Device: MRI-guided stereotactic body radiotherapyPatients with oligometastatic peritoneal carcinomatosis will receive MRI-guided stereotactic body radiotherapy (MRIgSBRT) delivered with a hybrid MRI-linear accelerator using online adaptive planning and real-time tumor tracking. Treatment dose will range from 30 to 50 Gy in 5 fractions according to clinical judgment and organ-at-risk constraints. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (8 listed)
- Age ≥18 years
- ECOG performance status 0-2
- Life expectancy ≥6 months
- Up to 5 MRI-visible peritoneal nodules
- PCI ≤20
Key exclusion criteria (6 listed)
- Diffuse peritoneal carcinomatosis
- Psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule (those conditions should be discussed with the patient before registration in the trial)
- Significant comorbidities (such as: severe cardiac or coagulative disease, moderate or severe
- restrictive/obsiructive lung deficit, severe cognitive impairment, moderate and severe renal and hepatic impairment.
- Pregnancy or breastfeeding
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 |
|---|---|---|
| MRI-guided stereotactic body radiotherapyPatients will receive MRI-guided stereotactic body radiotherapy (MRIgSBRT) delivered using a hybrid MRI-linear accelerator with online adaptive planning and real-time tumor tracking. Treatment will consist of 30-50 Gy delivered in 5 fractions according to clinical judgment, target characteristics, and organ-at-risk constraints. Daily adaptive replanning may be performed to account for anatomical changes and optimize dose delivery in patients with oligometastatic peritoneal carcinomatosis. | Device | MRI-guided SBRT |
Primary outcome
Radiological Response Rate (RR)
Time frame: Up to 12 months after completion of MRIgSBRT
RR: The response rate will be calculated as the proportion of patients achieving a complete or partial radiological response out of the total number of evaluable patients according to RECIST 1.1 criteria
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 18 May 2026.
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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.
Luca Boldrini principal investigator
Fondazione Policlinico Universitario Agostino Gemelli IRCCS
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing MRI-guided stereotactic body radiotherapy in people with Peritoneal Carcinomatosis and Oligometastatic Disease, run by Fondazione Policlinico Universitario Agostino Gemelli IRCCS at 1 site in Italy.
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 8 inclusion and 6 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 18 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. 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.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
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 Luca Boldrini (+390630158195, luca.boldrini@policlinicogemelli.it), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Radiological Response Rate (RR) (time frame: Up to 12 months after completion of MRIgSBRT). 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 18 May 2026.