Comparison of [68Ga]Ga-CTR-FAPI and 18F-FDG PET/MRI for Lymph Node Staging in Rectal Cancer

NCT07552207 | Not Yet Recruiting

• 1 other identifier: PKUCH_R12
• Study Type: interventional
• Target: 30
• Locations: 0 countries
• Sites: N/A

Brief 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. 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.

Conditions

Rectal Cancer; Lymph Node Metastases; PET / MR

Keywords

PET/MR; [68Ga]Ga-CTR-FAPI; 18F-FDG; Lymph Node Staging; Radiomics

Outcome Measures

Primary Outcomes (1)

• 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.

  Up to 30 days post-surgery

Secondary Outcomes (2)

• False Positive and False Negative Rates

  Up to 30 days post-surgery

• Correlation Between Radiomics Features and Tumor Microenvironment

  Up to 30 days post-surgery

Study Arms (1)

Rectal Cancer Patients

EXPERIMENTAL

Patients with confirmed middle to high rectal adenocarcinoma who are scheduled for radical surgery.

Diagnostic Test: PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI

Interventions

PET/MRI with 18F-FDG and [68Ga]Ga-CTR-FAPI DIAGNOSTIC_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).

Rectal Cancer Patients

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Peking University Cancer Hospital & Institute: lead

MeSH Terms

Conditions

Rectal Neoplasms; Lymphatic Metastasis

Condition Hierarchy (Ancestors)

Colorectal Neoplasms; Intestinal Neoplasms; Gastrointestinal Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Digestive System Diseases; Gastrointestinal Diseases; Intestinal Diseases; Rectal Diseases; Neoplasm Metastasis; Neoplastic Processes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Minghe Zhao

CONTACT

0086-15600896700; dzhao3163@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 20, 2026
• First Posted: April 27, 2026
• Study Start: April 1, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2028
• Last Updated: May 4, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share