An observational study in Metastatic Breast Cancer, sponsored by Sun Yat-sen University. Recruiting at 26 sites in 2 countries. Open to female participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-05-22.
Sponsored by Sun Yat-sen University · Observational
The purpose of this observational study is to learn about the HER2 heterogeneity and its impact on benefit from trastuzumab deruxtecan in metastatic breast cancer. The main question it aims to answer is:
- Does the heterogeneity of HER2 expression level and spatial distribution in different tissues affect the efficacy of trastuzumab deruxtecan in metastatic breast cancer?
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's planned enrollment of 800 is above the median of 184 across 2,642 observational studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Sun Yat-sen University is the lead sponsor of 1,644 studies on the registry; 602 are open to participants now.
Counted across the registry records on this site, refreshed daily.
This study is a multicenter, retrospective study led by the Sun Yat-sen University Cancer Center. A total of 16 centers are planned to participate in the study, and it aims to include patients with advanced or locally unresectable breast cancer who have received treatment with T-DXd.
Exclusion Criteria:
Drug: Trastuzumab Deruxtecan
The patients received Trastuzumab Deruxtecan at a dose of 5.4 mg/kg every 3 weeks until disease progression or unacceptable adverse effects occurred.
Progression-free survival (PFS)
Progression-free survival (PFS) is defined as the time from T-DXd treatment initiation to disease progression or death from any cause.
Time frame: From date of T-DXd treatment initiation until the date of first documented disease progression or date of death from any cause, whichever came first, assessed up to 60 months.
Overall survival (OS)
Overall survival (OS) is defined as the time from treatment initiation to death from any cause.
Time frame: From date of T-DXd treatment initiation until the date of death from any cause, assessed up to 60 months.
Objective response rate (ORR)
The Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) was used as the standard for evaluating treatment response to T-DXd. The response was evaluated based on the change in the tumor relative to baseline and was categorized as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). Objective response rate (ORR) is defined as the proportion of patients who achieved CR or PR.
Time frame: From screening and every 2-6 weeks up to progressive disease, or unacceptable toxicity, assessed up to 60 months.
Disease control rate (DCR)
The Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) was used as the standard for evaluating treatment response to T-DXd. The response was evaluated based on the change in the tumor relative to baseline and was categorized as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). Disease control rate (DCR) was defined as the proportion of patients who achieved CR, PR, or SD.
Time frame: From screening and every 2-6 weeks up to progressive disease, or unacceptable toxicity, assessed up to 60 months.
Clinical benefit rate (CBR)
The Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) was used as the standard for evaluating treatment response to T-DXd. The response was evaluated based on the change in the tumor relative to baseline and was categorized as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). The clinical benefit rate (CBR) was defined as the proportion of patients who achieved CR, PR, or SD for at least 24 weeks.
Time frame: From screening and every 2-6 weeks up to progressive disease, or unacceptable toxicity, assessed up to 60 months.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Sun Yat-sen University