This is a prospective observational study to refine and validate risk stratification algorithms aimed at identifying elderly patients at higher risk of developing cardiotoxicity (us-ing risk factors and potential blood and stool biomarkers) and at assessing whether integrated patient-oriented behavioral and psychological interventions can mitigate, prevent or delay the onset of cardiotoxicity from chemotherapy.

This is a prospective observational study for women with diagnosis of Breast Cancer (BC) who will undergo neoadjuvant and/or adjuvant treatment:

1. Women ≥ 60 years with a diagnosis of HER2-positive early/locoregional breast cancer with anti-HER2 therapy (trastuzumab or trastuzumab and pertuzumab)
2. Women ≥ 60 years with a diagnosis of early/locoregional breast cancer who will un-dergo neoadjuvant and/or adjuvant treatment with regimens including anthracy-clines and/or taxanes
3. Women ≥60 years with a diagnosis of early/locoregional breast cancer who will un-dergo neoadjuvant and/or adjuvant treatment with endocrine therapies +/- CDK 4/6 inhibitors
4. Women ≥ 60 years with HER2-positive metastatic breast cancer who will undergo first-line therapy with anti-HER2 therapy (trastuzumab or trastuzumab and per-tuzumab +/- chemotherapy).

The study primary objective is to evaluate the onset of cardiotoxicity, where: subclinical car-diotoxicity is defined as preserved Left Ventricular Ejection Fraction (LVEF).

All patients will receive, in addition to standard of care, supportive care. Patients in the control and in the intervention group will receive wearable and will be invited to complete the mobile ePsycHeart evaluation. ePsycHeart will assess patients' intrinsic capacity indicators that may be associated with including

1. psycho cognitive states (psychological and emotional states, QoL, cognitive function and memory, perceptions of aging, environmental and social factors),
2. mobility and locomotion (distance, balance, gait speed), and
3. vitality (exercise, electrocardiogram (ECG), Heart Rate Variability (HRV), grip strength, nutritional/energy state, sleep, fatigue), will be performed by means of sensors, wearables, electronic devices and validated patient reported outcome- and experience measures.

In addition, patients in the intervention group will receive the eHealtHeart: Behavioral and psychological interventions will be delivered to the intervention arm via the eHealtHeart mobile application to mitigate potential risk factors associated with cardiotoxicity and deterioration of QoL. eHealtHeart interventions will target patients and care givers aiming at improving patients' intrinsic capacity including psychological inter-ventions (e.g. emotional, dispositional states, biofeedback self-regulation, best possible self), cognitive stim-ulation (e.g. cognitive restructuring plus card games to improve memory and executive functions), sensory screening, physical activity and performance exercises, vision and hearing suggestions, dietary guidance on nutrition, guidance to improve management of urinary inconti-nence (e.g. alerts, self-monitoring) and falls together with providing education and support to caregivers. At month 6 the patient will have to return the wearables used for the study.

Inclusion Criteria:

1. Women ≥ 60 years with a diagnosis of early/locoregional breast cancer who will undergo neoadju-vant and/or adjuvant treatment with regimens including anthracyclines and/or taxanes.
2. Women ≥ 60 years with a diagnosis of HER2-positive locoregional breast cancer who will undergo neoadjuvant and/or adjuvant treatment with anti-HER2 therapy (trastuzumab or trastuzumab and pertuzumab).
3. Women ≥ 60 years with a diagnosis of early/locoregional breast cancer who will undergo neoadju-vant and/or adjuvant treatment with endocrine therapies +/- CDK 4/6 inhibitors.
4. Women ≥ 60 years with HER2-positive metastatic breast cancer who will undergo first-line therapy with anti-HER2 therapy (trastuzumab or trastuzumab and pertuzumab +/- chemotherapy).
5. Women with age ≥ 60 years before starting the aforementioned treatment for breast cancer.
6. Women eligible ≥ 60 years who will undergo first-line therapy in the metastatic setting with any type of treatment (chemotherapy, immunotherapy, biological agents).
7. Willingness and ability to comply with scheduled visits, laboratory tests, and other trial procedures
8. Written informed consent.
9. Participant affiliated to a social security system.
10. Life expectancy of at least 12 months.

Exclusion Criteria:

1. Age < 60 years.
2. Diagnosed severe psychiatric or neurological disorders that might impair the ability to give informed consent.

The prospective clinical study will enroll a total of 750 breast cancer patients over 12 months.