This is a multi-center, observational study. Patients who will participate, are participating or have participated in Daichi Sankyo INC sponsored Ds8201-A-U301 and Ds8201-A-U302 trials will be asked to participate to HER2-PREDICT study offering them a new informed consent.
After signing the informed consent form:
- For patients who have already begun dosing in Daichi Sankyo INC sponsored Ds8201-A-U301 and Ds8201-A-U302 trials, an archival metastatic biopsy will be requested for inclusion purposes.
- For patients who have not yet dosed in Daichi Sankyo INC sponsored Ds8201-A-U301 and Ds8201-A-U302 trials eligible patients will undergo a fresh biopsy of a metastatic site. If not feasible, archival sample from metastatic site will be accepted. Blood samples will be collected from eligible patients for biomarker analyses.
In both cases, a breast tumor sample will be acceptable for those patients who are diagnosed with de novo metastatic breast cancer.
Exceptionally, for those patients who do not have a metastatic sample or the possibility of obtaining it in the cases mentioned above, the possibility of sending a sample of the primary tumor for inclusion purposes may be requested. SOLTI will confirm if the patient can be included.
In order to identify mRNA ERBB2 levels, we will evaluate by gene expression tumor samples from these patients.
