TROPION Breast Respond in 1L TNBC

There are no real-world data available on the effectiveness and safety of Dato-DXd in adult patients with unresectable or metastatic triple-negative breast cancer who are not candidates for PD-1/PD-L1 inhibitor therapy. This NIS will investigate the effectiveness of Dato-DXd, the demographic and clinical characteristics of the patients, and treatment patterns.

Key Inclusion Criteria: * Age ≥18 years at the time of screening * Histologically or cytologically documented locally recurrent inoperable or metastatic TNBC defined as: * Negative for ER * Negative for progesterone receptor * Negative for HER2 with 0 or 1+ intensity on IHC or 2+ intensity on IHC and negative by in situ hybridization per the ASCO-CAP HER2 guideline * Patients must not be a candidate for PD-1/PD-L1 inhibitor therapy, defined as either the tumor was PD-L1 negative (Combine Positive Score (CPS \< 10), or it was PD-L1 positive (CPS ≥ 10 ) and: have relapsed after prior PD-1/PD-L1 inhibitor therapy for early-stage breast cancer or patient was not eligible for IO therapy due to comorbidities precluding PD-1/PD-L1 inhibitor therapy * Patients had not received prior chemotherapy or other systemic anti-cancer therapy for unresectable or metastatic breast cancer * Decision to newly initiate therapy Dato-DXd according to the physician's choice per SmPC. If the patient received just one dose of Dato-DXd already, the patient can still be included retrospectively * Written and signed Informed Consent (ICF) to participate in the study Key Exclusion Criteria: * Pregnancy or breastfeeding * Patients who at time of data collection for this study are participating in an interventional study regardless of whether the study is double blind or open label. Patients that have participated in an interventional study which is completed but remain blinded are also excluded.