An Observational Real-world Study to Evaluate the Impact of Dermatological Toxicities on the Quality of Life in Patients With Early Breast Cancer Treated With Adjuvant Endocrine Therapy - BCARE (Breast Cancer Adjuvant Real-world Evaluation of Dermatological Adverse Events)

The DLQI consists of 10 questions concerning patients' perception of the impact of skin diseases on different aspects of their health-related quality of life over the last week, including symptoms, feelings, daily activities, leisure, work, school, personal relationships, and treatment.

The primary endpoint is the rate of patients with a DLQI score ≥ 6. The DLQI is calculated by summing the score of each question resulting in a maximum of 30 and a minimum of 0. The higher the score, the more quality of life is impaired:

• 0 - 1 corresponds to no effect at all on patient's life,
• 2 - 5 corresponds to small effect on patient's life,
• 6 - 10 corresponds to moderate effect on patient's life,
• 11 - 20 corresponds to very large effect on patient's life,
• 21 - 30 corresponds to extremely large effect on patient's life.

The Skindex-16 includes items distributed across three domains symptoms (items 1 to 4), emotions (items 5 to 11) and functioning (items 12 to 16) and are answered on a seven-point Likert scale (varying from 0-never bothered, to 6-always bothered), which represents the frequency with which the skin problem bothered the respondent during the past week. This is a 0-100 scale, higher the score, the more quality of life is impaired.

The Hairdex is a valuable tool for evaluating disease-specific QoL in patients with hair disorders. It consists of 48 questions across five sections: symptoms, functioning, emotions, self-confidence, and stigmatization. Each question is self-graded on a scale of 0-4, with a score of 4 indicating the most severe change from a patient's baseline quality of life.

The ItchyQoL is a questionnaire used to measure the QoL in patients with chronic pruritus. It is composed of 22 items regarding symptoms, functions, emotions and self-perception, and is currently under

• Type of toxicity
• Surface area involved (except for nails and oral dryness)
• Start date
• Clinical grading of the toxicity

• Age, gender, weight, height
• Menopausal status
• Date of cancer diagnosis
• Primary tumor location
• T stage
• Prior therapies for breast cancer (type, agent name, start date, stop date)
• Endocrine therapy (agent name, start date) for breast cancer
• Current dermatological care and sun-protective behaviors

• Type of dermatological toxicity
• Surface area (except for nails and oral dryness)
• Start date and end date
• Grade of the toxicity, if available
• Change in hormonal treatment (adaptation, interruption), if applicable

• Age repartition by class (< 35 years old, 35-50, 50-65, > 65 years old)
• Menopause status
• Therapeutical choice before the 2/3 years of adjuvant endocrine therapy

• Radiotherapy (yes / no)
• Chemotherapy (yes / no), if yes, the information whether taxane was received or not will be collected
• Adjuvant (yes/no)
• Neoadjuvant (yes/no)
• Target therapy (yes / no)
• Type of adjuvant endocrine therapy

Analyses of primary, secondary, and exploratory outcomes may be performed for some or all of these subgroups, subject to pertinence and the number of patients in each subgroup.