Rectal CancerPKUCH-R12NCT07552207
Comparison of [68Ga]Ga-CTR-FAPI and 18F-FDG PET/MRI for Lymph Node Staging in Rectal Cancer
A study testing PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI in people with Rectal Cancer and Lymph Node Metastases, run by Peking University Cancer Hospital & Institute.
Trial summary
This is a prospective, single-center, diagnostic study designed to compare the accuracy of [68Ga]Ga-CTR-FAPI PET/MRI and [18]F-FDG PET/MRI for the detection of lymph node metastasis in patients with initially untreated, resectable middle to high rectal cancer. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Rectal Cancer, Lymph Node Metastases, PET / MR
- What is being tested?
- PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 30 participants
- Where
- No sites listed yet
- Study dates
- 1 Apr 2026to 31 Dec 2028
- 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 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Confirmed rectal adenocarcinoma by pathological biopsy.
- Lower margin of the tumor is ≥ 5 cm and ≤15 cm from the anal verge.
- Planned to undergo radical surgery.
- ECOG performance status score ≤ 2.
- Patient is willing to undergo PET/MRI examination.
Who cannot join
- History of pelvic radiotherapy or chemotherapy.
- Concurrent with other malignant tumors or active infections.
- Pregnant or unable to sign the informed consent form.
- Claustrophobia or inability to tolerate MRI examinations due to other reasons.
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: Comparison of the Diagnostic Efficacy of [68Ga]Ga-CTR-FAPI PET/MRI and 18F-FDG PET/MRI for Lymph Node Metastasis in Middle to High Rectal Cancer
This is a prospective, single-center, diagnostic study designed to compare the accuracy of [68Ga]Ga-CTR-FAPI PET/MRI and [18]F-FDG PET/MRI for the detection of lymph node metastasis in patients with initially untreated, resectable middle to high rectal cancer. The study aims to evaluate whether [68Ga]Ga-CTR-FAPI PET/MRI provides higher sensitivity and specificity than traditional 18F-FDG PET/MRI at both the patient level and the lymph node level.
Read the detailed description
Accurate preoperative staging of colorectal cancer is crucial for formulating treatment plans and improving patient prognosis. While conventional MRI and 18F-FDG PET/MRI are utilized, they face limitations such as false positives due to inflammatory lymph nodes or fibrotic scars. Fibroblast activating protein inhibitor (FAPI) specifically targets tumor-associated fibroblasts, potentially reducing false-positive rates by avoiding non-specific uptake in inflammatory areas.
This study aims to cross-validate the diagnostic efficacy of these two probes through a precise imaging-pathology matching technique. All enrolled patients will sequentially undergo both [68Ga]Ga-CTR-FAPI PET/MRI and 18F-FDG PET/MRI within 30 days prior to radical surgery. Following surgery, fresh mesorectal specimens will be precisely sectioned and matched to preoperative anatomical imaging maps. By leveraging a well-established node-by-node matching and identification methodology with high accuracy, this study ensures the execution of spatial correlation between preoperative radiologic imaging and postoperative microscopic pathology. Through mapping individual lymph nodes, the study will analyze the root causes of false positives and negatives, and extract radiomics features to evaluate their correlation with the tumor microenvironment (e.g., fibroblast density, Ki-67 index).
- Conditions
- Rectal Cancer, Lymph Node Metastases, PET / MR
- Being tested
- PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI
- Keywords
- PET/MR, [68Ga]Ga-CTR-FAPI, 18F-FDG, Lymph Node Staging, Radiomics
- Medical subject headings
- Rectal Neoplasms, Lymphatic Metastasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPIDiagnostic test
Diagnostic Test: 18F-FDG PET/MRI
Description: Patients receive an intravenous injection of 18F-FDG (3.7-5.5 MBq/kg).
Diagnostic Test: [68Ga]Ga-CTR-FAPI PET/MRI
Description: Patients receive an intravenous injection of [68Ga]Ga-CTR-FAPI (1.8-3.7 MBq/kg).
| Study group | Role | What they receive |
|---|---|---|
| Rectal Cancer Patients | Experimental | Patients with confirmed middle to high rectal adenocarcinoma who are scheduled for radical surgery. Receives: Diagnostic Test: PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI |
What is being measured
The primary outcome is the main question the study is designed to answer.
Sensitivity and Specificity of Lymph Node Metastasis Detection
Comparison of the sensitivity and specificity of [68Ga]Ga-CTR-FAPI and 18F-FDG PET/MRI in determining lymph node metastasis at both the individual lymph node level and the patient level. Sensitivity is defined as the proportion of imaging-positive and pathology-positive nodes out of all pathology-positive nodes. Specificity is defined as the proportion of imaging-negative and pathology-negative nodes out of all pathology-negative nodes.
Measured: Up to 30 days post-surgery
Secondary outcomes (2)
False Positive and False Negative Rates
Analysis of the false positive and false negative rates of FAPI and FDG imaging, exploring underlying pathological bases such as inflammation or micrometastasis.
Measured: Up to 30 days post-surgery
Correlation Between Radiomics Features and Tumor Microenvironment
Extraction of lymph node radiomics features to evaluate their association with tumor microenvironmental markers, determined via automatic immunohistochemistry scoring.
Measured: Up to 30 days post-surgery
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Apr 2026
- Study start1 Apr 2026 (estimated)
- Primary completion31 Dec 2027 (estimated)
- Study completion31 Dec 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Rectal CancerStudies of the same condition, open and under way.
- More trials run by Peking University Cancer Hospital & InstituteThe 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
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Peking University Cancer Hospital & Institute
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07552207
- Sponsor's protocol ID
- PKUCH_R12
- Acronym
- PKUCH-R12
- Status last verified
- Jan 2026
- First submitted
- 20 Apr 2026
- Last updated
- 4 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Diagnostic Efficacy of [68Ga]Ga-CTR-FAPI PET/MRI and 18F-FDG PET/MRI for Lymph Node Metastasis in Middle to High Rectal Cancer
- ClinicalTrials.gov ID
- NCT07552207
- Acronym / sponsor ID
- PKUCH-R12 / PKUCH_R12
- Conditions
- Rectal Cancer, Lymph Node Metastases, PET / MR
- Keywords
- PET/MR, [68Ga]Ga-CTR-FAPI, 18F-FDG, Lymph Node Staging, Radiomics
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Peking University Cancer Hospital & InstituteUniversity, hospital or other
- Study start
- 1 Apr 2026 (estimated)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 31 Dec 2028 (estimated)
- First posted
- 27 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.
This is a prospective, single-center, diagnostic study designed to compare the accuracy of [68Ga]Ga-CTR-FAPI PET/MRI and [18]F-FDG PET/MRI for the detection of lymph node metastasis in patients with initially untreated, resectable middle to high rectal cancer. The study aims to evaluate whether [68Ga]Ga-CTR-FAPI PET/MRI provides higher sensitivity and specificity than traditional 18F-FDG PET/MRI at both the patient level and the lymph node level.
Detailed description
Accurate preoperative staging of colorectal cancer is crucial for formulating treatment plans and improving patient prognosis. While conventional MRI and 18F-FDG PET/MRI are utilized, they face limitations such as false positives due to inflammatory lymph nodes or fibrotic scars. Fibroblast activating protein inhibitor (FAPI) specifically targets tumor-associated fibroblasts, potentially reducing false-positive rates by avoiding non-specific uptake in inflammatory areas.
This study aims to cross-validate the diagnostic efficacy of these two probes through a precise imaging-pathology matching technique. All enrolled patients will sequentially undergo both [68Ga]Ga-CTR-FAPI PET/MRI and 18F-FDG PET/MRI within 30 days prior to radical surgery. Following surgery, fresh mesorectal specimens will be precisely sectioned and matched to preoperative anatomical imaging maps. By leveraging a well-established node-by-node matching and identification methodology with high accuracy, this study ensures the execution of spatial correlation between preoperative radiologic imaging and postoperative microscopic pathology. Through mapping individual lymph nodes, the study will analyze the root causes of false positives and negatives, and extract radiomics features to evaluate their correlation with the tumor microenvironment (e.g., fibroblast density, Ki-67 index).
Study design
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Rectal Cancer Patients | Experimental | Diagnostic Test: PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPIPatients with confirmed middle to high rectal adenocarcinoma who are scheduled for radical surgery. |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Confirmed rectal adenocarcinoma by pathological biopsy.
- Lower margin of the tumor is ≥ 5 cm and ≤15 cm from the anal verge.
- Planned to undergo radical surgery.
- ECOG performance status score ≤ 2.
- Patient is willing to undergo PET/MRI examination.
Key exclusion criteria (4 listed)
- History of pelvic radiotherapy or chemotherapy.
- Concurrent with other malignant tumors or active infections.
- Pregnant or unable to sign the informed consent form.
- Claustrophobia or inability to tolerate MRI examinations due to other reasons.
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 |
|---|---|---|
| PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPIDiagnostic Test: 18F-FDG PET/MRI Description: Patients receive an intravenous injection of 18F-FDG (3.7-5.5 MBq/kg). Diagnostic Test: [68Ga]Ga-CTR-FAPI PET/MRI Description: Patients receive an intravenous injection of [68Ga]Ga-CTR-FAPI (1.8-3.7 MBq/kg). | Diagnostic test | Rectal Cancer Patients |
Primary outcome
Sensitivity and Specificity of Lymph Node Metastasis Detection
Time frame: Up to 30 days post-surgery
Comparison of the sensitivity and specificity of [68Ga]Ga-CTR-FAPI and 18F-FDG PET/MRI in determining lymph node metastasis at both the individual lymph node level and the patient level. Sensitivity is defined as the proportion of imaging-positive and pathology-positive nodes out of all pathology-positive nodes. Specificity is defined as the proportion of imaging-negative and pathology-negative nodes out of all pathology-negative nodes.
2 secondary outcomes
False Positive and False Negative Rates
Time frame: Up to 30 days post-surgery
Correlation Between Radiomics Features and Tumor Microenvironment
Time frame: Up to 30 days post-surgery
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 4 May 2026.
- Individual participant dataSharing planned: No
Related trials for Rectal Cancer
Not yet recruitingPhase 1
Hepatic Artery Infusion of Carfilzomib in Participants With Liver Metastatic Disease Previously Treated With Hepatic Artery Infusion Pump Therapy
Colorectal Neoplasms, Neoplasms
Active, not recruiting
Streamlined Geriatric and Oncological Evaluation Based On IC Technology
Breast Cancer, Comorbidities and Coexisting Conditions
RecruitingObservational study
Pre- and On-treatment Multi-omics Profiling of Locally Advanced Rectal Cancer
Rectal Neoplasms
Enrolling by invitationObservational study
Natural History Study of Early Life Exposures in Agriculture (ELEA)
Prostate Cancer, Leukemia
RecruitingPhase 2
Tislelizumab in People With Colorectal Cancer
Colorectal 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.
Questions about this trial
What is this clinical trial studying?
A study testing PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI in people with Rectal Cancer and Lymph Node Metastases, run by Peking University Cancer Hospital & Institute.
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 5 inclusion and 4 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 4 May 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 Minghe Zhao (0086-15600896700, dzhao3163@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Sensitivity and Specificity of Lymph Node Metastasis Detection (time frame: Up to 30 days post-surgery). 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 4 May 2026.