Application of 68Ga-Pentixafor PET/CT for Thymoma

Study Overview
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Brief Summary
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Chemokine receptor CXCR4 was expressed in T cells and CXCR4-targeting molecular imaging- 68Ga-Pentixafor PET/CT could be a promising technique to evaluate the extent of thymoma with higher accuracy. This prospective study is going to investigate whether metabolic characterization by 68Ga-Pentixafor PET/CT may be superior for diagnosis, distinguish evaluation for thymoma.

Detailed Description
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Thymoma is 1 rare type of tumor developed on the thymic epithelium; patients with thymoma also might have myasthenia gravis (MG). Because of the scarcity and complexity of MG-associated thymoma, its pathogenesis and etiology still remain unclear nowadays. The expression of C-X-C chemokine receptor type 4 (CXCR4) is absent or low in most healthy tissues but highly expressed in various types of tumors. CXCR4 might contribute to the clinical cancer progression, and CXCR4 could be a valuable prognostic biomarker in the therapy of MG-associated thymoma.

Official Title
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Chemokine Receptor CXCR4-targeting PET Imaging for Thymoma

Conditions
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Thymoma

Intervention / Treatment
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* Drug: 68Ga-Pentixafor


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: suspected or confirmed untreated thymoma patients signed written consent. Exclusion Criteria: pregnancy breastfeeding known allergy against Pentixafor any medical condition that in the opinion of the investigator,may significantly interfere with study compliance.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 68Ga-Pentixafor, PET/CT<br>Inject 68Ga-Pentixafor and then perform PET/CT scan. | Drug: 68Ga-Pentixafor<br>* Intravenous injection of one dosage of 74-185 MBq(2-5 mCi) 68Ga-Pentixafor. Tracer doses of 68Ga- Pentixafor will be used to image lesions of thymoma by PET/CT.<br>* Other names: 68Ga-CXCR4;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| SUVmax and SUVmean | SUVsof focal lesions are measured on 68Ga-Pentixafor PET/CT. The SUVs of the blood pool and muscle are defined as the background activity on the condition that there is no focally hypermetabolic disease. | through study completion, an average of 1.5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diagnostic value | Diagnostic value of 68Ga-Pentixafor PET/CT for thymoma in comparison with 18F-FDG PET/CT or CT or MRI. | through study completion, an average of 1.5 years | 
| Diagnostic value in special type of thymoma | Diagnostic value of 68Ga-Pentixafor PET/CT in special type thymoma (A\AB\B\C subtypes) | through study completion, an average of 1.5 years | 
| Diagnostic value in thymoma and other masses | Diagnostic value of 68Ga-Pentixafor PET/CT in thymoma and other anterior mediastinal mass. | through study completion, an average of 1.5 years | 
| CXCR4 expression and SUV | Correlation between CXCR4 expression and SUV in PET | through study completion, an average of 1.5 years |