European Treatment Patterns and Outcomes Associated With First-Line CDK4/6 Inhibition and Hormonal Therapies

Inclusion Criteria

• •Is male or female
• •Has histologically or cytologically confirmed breast cancer diagnosis (HR+/HER2- breast cancer)
• •Has received a diagnosis of locally advanced breast cancer not amenable to curative radiation or surgical cure or of metastatic breast cancer (i.e., advanced breast cancer \[ABC\]); diagnosis may be de novo (initial diagnosis at ABC stage) or recurrent from earlier-stage disease (initial diagnosis of earlier-stage disease with subsequent progression to advanced disease)
• •Has initiated a required first-line therapy of interest: Palbociclib plus AI as first-line therapy for ABC between September 1, 2016, and July 31, 2020, or AI monotherapy as first-line therapy for ABC between January 1, 2010,, and July 31, 2020
• •Was aged 18 years or older at the time of diagnosis of ABC
• •Is living or deceased at the time of record abstraction
• •Has a complete medical record, covering treatment for ABC, including any transfer record from other facilities (if applicable) that is available to the abstractor for data abstraction