HER2 Expression of HER2 Affibody-based PET/CT to Predict Response in Bladder Cancer Patients Treated With ADC

Inclusion Criteria: 1. Aged # 18 years old; ECOG 0 or 1; 2. Is unresectable or metastatic; 3. Patients with HER2 positive or suspicious positive tumors; 4. was previously treated with trastuzumab and taxane in the advanced setting or progressed within 6 months after neoadjuvant or adjuvant treatment involving a regimen including trastuzumab and taxane; 5. Has adequate cardiac, bone marrow, renal, hepatic and blood clotting functions; 6. Receives anti-HER2 ADC treatment 7. Life expectancy \> 3 months Exclusion Criteria: 1. Significant hepatic or renal dysfunction; 2. Is pregnant or ready to pregnant; 3. Cannot keep their states for half an hour; 4. Refused to join the clinical research; 5. Suffering from claustrophobia or other mental disorders; 6. Any other situation that researchers considered it unsuitable to participate in the trial.