This is a single arm prospective, observational multi-centre study in patients with HER-2 positive breast cancer who have completed concurrent chemotherapy with pertuzumab and trastuzumab administered IV and are currently receiving or will be receiving maintenance therapy with PH FDC SC and have at least 6 cycles of therapy expected with PH FDC SC to conclude pre-established oncological treatment.

Treatment of the patients will not be determined or assigned by study procedures but will be based on normal clinical practice. Only data available per clinical practice will be collected within this study. The treatment decision must have been taken prior to and irrespective of patient's inclusion in the study.

Primary objective

• The primary objective of the study is to evaluate the safety of pertuzumab and trastuzumab (PH) fixed-dose combination (FDC) for subcutaneous (SC) administration in patients with HER-2 positive breast cancer who have completed concurrent chemotherapy with pertuzumab and trastuzumab administered intravenously (IV) and are currently receiving or will be receiving maintenance therapy with PH FDC SC.

Secondary objectives

The secondary exploratory objectives of the study are:

• To assess the patient's social cost saving by means of a specific questionnaire;
• To assess the patient's health related quality of life (HRQOL).

Inclusion Criteria:

• Written informed consent of the patient;
• Female and male patients aged ≥ 18 years (no upper limit);
• Patients with HER-2 positive breast cancer, who have completed concurrent chemotherapy with pertuzumab and trastuzumab IV and are currently receiving or will be receiving maintenance therapy with PH FDC SC according to locally approved indication;
• Patients with expected at least 6 cycles of therapy with PH FDC SC to conclude pre-established oncological treatment;

Exclusion Criteria:

• Life expectancy < 6 months;
• Presence of any contraindication with regard to treatment with PH FDC SC as specified in the corresponding Summary of Product Characteristics (SmPCs) approved in Italy;
• Concomitant participation in another interventional or non-interventional trial.
• Patients with less than 6 remaining cycles of therapy with PH FDC SC to conclude pre-established oncological treatment

patients with HER-2 positive breast cancer who have completed concurrent chemotherapy with pertuzumab and trastuzumab administered IV and are currently receiving or will be receiving maintenance therapy with PH FDC SC and have at least 6 cycles of therapy expected with PH FDC SC to conclude pre-established oncological treatment.

It is not yet known if there will be a plan to make IPD available