Using advanced PET imaging to evaluate early responses in rectal cancer patients receiving immunotherapy

68Ga-FAPI-04 PET Imaging in Early Response Evaluation of Rectal Cancer Patients Treated With Immunotherapy: A Single-center Clinical Study

Not applicable Interventional Wuhan Union Hospital, China · NCT05999227

This study is testing a new type of PET imaging to see if it can better show how rectal cancer patients are responding to immunotherapy and chemotherapy.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment20 (estimated)
Ages18 Years and up
SexAll
SponsorWuhan Union Hospital, China Academic / other
Drugs / interventionsradiation, chemotherapy, immunotherapy
Locations1 site (Wuhan, Hubei)
Trial IDNCT05999227 on ClinicalTrials.gov

What this trial studies

This prospective study aims to assess the effectiveness of 68Ga-FAPI-04 PET imaging in evaluating early responses in rectal cancer patients undergoing immunotherapy. Patients with confirmed rectal cancer will receive both 68Ga-FAPI-04 and 18F-FDG PET imaging before treatment and after a short course of radiotherapy followed by two cycles of neoadjuvant chemotherapy and immunotherapy. The study will compare the efficacy of these imaging modalities in detecting treatment responses, particularly in distinguishing between true progression and pseudoprogression. A total of 20 patients will be recruited for this evaluation.

Who should consider this trial

Good fit: Ideal candidates are treatment-naïve patients with histologically confirmed T3-4N0M0 or T1-4N+M0 rectal adenocarcinoma.

Not a fit: Patients with a history of anti-PD-1 or PD-L1 treatments, pelvic radiation, or autoimmune diseases may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to more accurate early detection of treatment responses in rectal cancer, potentially improving patient outcomes.

How similar studies have performed: While FAP-targeted imaging has shown promise in predicting responses to immunotherapy, this specific approach is novel and has not been extensively tested in similar studies.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histologically confirmed T3-4N0M0 or T1-4N+M0 (according to the 8th edition of the International Union Against Cancer TNM staging system) rectal adenocarcinoma and treatment naïve;
* No severe hematologic, cardiac, pulmonary, hepatic, or renal functional abnormalities or immunodeficiency diseases;
* An Eastern Cooperative Oncology Group Performance Status of 0-1;
* Patients who agree to undergo 68Ga-FAPI-04 and 18F-FDG PET imaging.

Exclusion Criteria:

* Any experiences of anti-programmed death ligand 1 (PD-L1) or anti-PD-1 antibody treatment;
* A history of pelvic radiation;
* The presence of autoimmune disease;
* Hypersensitive to any monoclonal antibodies;
* History of interstitial lung disease;
* Active and uncontrolled infection.

Where this trial is running

Wuhan, Hubei

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Rectal Cancer
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.