The objective of the study is to construct a noninvasive approach 68Ga-TTP PET/CT to detect the TROP2 expression of tumor lesions in patients with breast tumors and evaluate the efficacy of ADC drug therapy.
Age 18-75 years old, male or female, ECOG score 0 or 1 points (see the table in Annex 2 for the score table);
Blood routine and liver and kidney function meet the following criteria: Blood routine: WBC ≥ 4.0×109 L or neutrophil ≥1.5×109 /L, PLT ≥ 100×109/L, Hb≥ 90 g/L; PT or APTT ≤ 1.5 ULN; Liver and kidney function: T-Bil ≤ 1.5×ULT(upper limit of normal), ALT and AST≤ 2.5 ULN or ≤ 5×ULT(subjects with liver metastasis), ALP ≤ 2.5 ULN(ALP ≤ 4.5 ULN if there is bone metastasis or liver metastasis); BUN ≤ 1.5×ULT, SCr ≤ 1.5×ULT;
Patients with confirmed or suspected breast cancer;
Expected survival ≥12 weeks;
Severe abnormal liver and kidney function;
Pregnant, pregnant and lactating women;
Can not lie flat for half an hour;
Unable to obtain informed consent;
Single group
18F-FDG
Drug\[18F\]FDG is administered intravenously as the comparator PET radiotracer. In the diagnostic validation cohort, participants undergo one \[18F\]FDG PET examination within 1 week of the \[68Ga\]Ga-TTP scan, with no treatment between scans. In the ADC response assessment cohort, participants undergo \[18F\]FDG PET imaging at the same three time points as \[68Ga\]Ga-TTP: before ADC therapy, after 2 cycles(each cycle is 21 days), and at disease progression. The planned administered activity is approximately 0.1-0.15 mCi/kg.
[68Ga]Ga-TTP
Drug\[68Ga\]Ga-TTP is a TROP2-targeted PET radiotracer administered intravenously for PET imaging. In the diagnostic validation cohort, participants undergo one \[68Ga\]Ga-TTP PET examination within 1 week of the comparator \[18F\]FDG scan. In the ADC response assessment cohort, participants undergo \[68Ga\]Ga-TTP PET imaging before ADC therapy, after 2 cycles of treatment(each cycle is 21 days), and at disease progression. The planned administered activity is approximately 0.05-0.1 mCi/kg.
Diagnostic performance of [68Ga]Ga-TTP PET compared with [18F]FDG PET for breast cancer lesions
To compare the diagnostic performance of \[68Ga\]Ga-TTP PET and \[18F\]FDG PET for breast cancer lesions, including sensitivity, specificity, accuracy, false-positive rate, and false-negative rate, using pathology and/or integrated follow-up assessment as reference standard.
Change in [68Ga]Ga-TTP uptake in relation to ADC treatment response
To evaluate the association between changes in tumor uptake on \[68Ga\]Ga-TTP PET (e.g., SUV or SUVmax) before treatment, after 2 cycles of TROP2-directed ADC therapy(each cycle is 21 days), and at disease progression, and clinical treatment response in patients with breast cancer receiving ADC therapy.assessed up to 24 months.
Correlation between [68Ga]Ga-TTP uptake and TROP2 expression in tumor tissue
To evaluate the correlation between standardized uptake values of \[68Ga\]Ga-TTP PET in target or suspected tumor lesions and TROP2 expression level in corresponding pathological tissue samples.
Biodistribution and temporal distribution pattern of [68Ga]Ga-TTP in patients
To assess the in vivo biodistribution, organ uptake, and temporal distribution characteristics of \[68Ga\]Ga-TTP in patients with breast cancer at different imaging time windows.
Pathological results of lesions suspected to be positive on [68Ga]Ga-TTP PET
To assess the pathological findings of lesions suspected to be positive on \[68Ga\]Ga-TTP PET imaging, including concordance with biopsy or surgical pathology when available.
Click on the lead sponsor to view all of their trials.
Peking University Cancer Hospital & Institute
Lead sponsor
Yunnan Cancer Hospital
Collaborator
