Real-world Study of HER2-overexpressed Advanced Solid Tumors After Progression of First-line Standard Therapy

Inclusion Criteria:

* Signing informed consent and agreeing to comply with study requirements;
* Age ≥18 years old, gender unlimited;
* ECOG physical status 0-2 points;
* Patients with locally advanced or metastatic solid tumors confirmed histologically or cytologically;Cohort1-2 cohort: patients who had received at least previous first-line standard therapy (HER2 IHC3+ or IHC2+/FISH+ patients with first-line trastuzumab (or its biosimilar) combined with chemotherapy (fluorouracil and/or platinum-based chemotherapy);IHC2+/FISH- patients with first-line Immunotherapy combined with chemotherapy (fluorouracil and/or platinum-based chemotherapy) or chemotherapy alone);In Cohort3 cohort, patients received at least the standard first-line treatment clearly recommended by the guidelines. Patients with clear disease progression confirmed by the investigator or documented history.
* HER2 overexpression was defined as 2+ or 3+ immunohistochemistry (both primary and metastatic tumor tissue were acceptable), and previous patient test results (confirmed by the investigator) or center test results were acceptable.
* Have measurable or evaluable lesions according to RECIST1.1 criteria;
* The investigator evaluated that the patients would benefit from the study treatment;
* Good compliance, willing and able to follow the trial and follow-up procedures;
* Have traceable patient medical records.

Exclusion Criteria:

* Known hypersensitivity or delayed allergic reactions to certain components of the study drug or similar drugs;
* Participating in any interventional clinical trials;
* The investigator assessed inappropriate inclusion.