Trop-2 Targeted PET Probes in Advanced TNBC

• Primary Objectives To evaluate the correlation between 89Zr-DFO-hSR7 uptake in tumor lesions and TROP2 expression in breast cancer tissues.

To compare the diagnostic efficacy of 89Zr-DFO-hSR7 and 18F-FDG in breast cancer lesions, including sensitivity, specificity, and accuracy.

To investigate the validity of 89Zr-DFO-hSR7 in assessing the efficacy of sacituzumab govitecan therapy for breast cancer.

• Secondary Objectives To clarify the in vivo distribution and metabolism of 89Zr-DFO-hSR7. To monitor resistance to sacituzumab govitecan therapy and explore potential resistance mechanisms.
• Primary Endpoints The relationship between changes in SUV values on 89Zr-DFO-hSR7 PET imaging before and after sacituzumab govitecan treatment and therapeutic response in breast cancer patients.

Pathological biopsy results corresponding to suspiciously positive lesions identified by 89Zr-DFO-hSR7 PET imaging.

• Secondary Endpoints The tumor-to-background ratio (TBR) of standardized uptake values (SUVs) of 89Zr-DFO-hSR7 in target lesions or suspected tumor lesions versus normal tissues within each time window.

To evaluate the in vivo biodistribution of 89Zr-DFO-hSR7 and its temporal changes.

To assess/compare the clinical utility of the probe in breast cancer patients.

Inclusion criteria

• Aged 18 - 75 years, male or female, with an ECOG score ≥ 2.
• Blood routine, liver and kidney functions meet the following standards:

• Blood routine: Total white blood cell count (WBC) ≥ 3.0×10⁹/L or neutrophil count (Neu) ≥ 1.5×10⁹/L, platelet count (PLT) ≥ 80×10⁹/L, hemoglobin (Hb) ≥ 80 g/L.
• Liver and kidney functions: Total bilirubin (T - Bil) ≤ 1.5×ULN (upper limit of normal value), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.5×ULN or ≤ 5×ULN (in case of liver metastasis), serum creatinine (SCr) ≤ 1.5×ULN.
• Subjects with advanced triple - negative breast cancer previously diagnosed by histopathological diagnosis and imaging evaluation.
• Expected survival time ≥ 12 weeks.
• Clinicians assess that TROP - 2 ADC is an appropriate treatment plan for the subject at present.
• There is at least one measurable target lesion in accordance with the RECIST 1.1 standard.
• Subjects for whom clinicians recommend PET/CT examination for breast tumor diagnosis and staging.
• Women of childbearing age (18 - 60 years old) must undergo a pregnancy test within 7 days before the start of the examination and the result is negative; Male and female subjects with fertility must agree to use effective contraceptive measures to ensure no pregnancy during the study period and within 3 months after the examination.
• The subject can fully understand and voluntarily participate in this experiment, sign the informed consent form, and have good follow - up compliance.

Exclusion criteria

• Severe abnormalities in liver and kidney functions;
• Women who are in the pre - pregnancy period, pregnant or lactating;
• Those who cannot lie flat for half an hour;
• Those who cannot provide informed consent;
• Those suffering from claustrophobia or other mental illnesses;
• Those known to be allergic to the investigational drugs or their excipients used in the study treatment;
• Other situations that the researchers consider make it inappropriate to participate in the trial.