A Study to Learn More About Tukysa Once it is Out in the Korean Market

The purpose of this study is to understand the safety of Tukysa (Tucatinib hemiethanolate) once it is out in the Korean market. Tukysa will be given to participants aged 18 or over in Republic of Korea. Surveillance Design Patients with the approved indication who are treated with TUKYSA within the local label will be enrolled. Adverse Events (AEs) will be collected in the usual practice during administration and for 28 days following cessation of TUKYSA, and ORR will be evaluated through radiographic imaging in the usual practice. The total follow-up period will not exceed 1 year. Safety Through the evaluation the safety profile of TUKYSA including important identified risks, Important potential risks, missing information, which are defined about TUKYSA in table2, will be examined. Drug safety is evaluated through the following items: Efficacy Drug efficacy will be evaluated through the BOR. The ORR which is defined as the proportion of the subjects in the analysis population who have best response as CR or PR will be presented. Surveillance for long-term use The follow-up period for each patient will vary according to tumor response, treatment of TUKYSA and others. Any patients who are treated with TUKYSA for more than or equal to 180 days including dose interruption will be evaluated for surveillance for long-term use.