Resource constraints

This observational disease registry is a prospective, national, non-interventional study designed to enroll participants who have received an initial diagnosis of unresectable, locally advanced (LA) or metastatic breast cancer (mBC), up to 6 months prior to registry enrolment. These participants will be prospectively followed for at least 5 years after study enrolment to evaluate their anti-cancer treatments. Data on participants' previous anti-cancer treatments for breast cancer will be collected retrospectively at study entry.

Inclusion Criteria:

- Initially diagnosed with HER2-positive unresectable LA/mBC no more than 6 months prior to enrolment, although they can have received anti-cancer treatment during that time

Exclusion Criteria:

There are no exclusion criteria for entry into this study.

Participants who have an initial diagnosis of unresectable LA/mBC made up to 6 months prior to registry enrolment.