Women in the Hauts-de-France region show higher breast cancer mortality despite no overall higher incidence, suggesting differences in the care pathway. This multicenter study will describe the overall time from the first warning sign to initiation of the first treatment, and will break down this delay into three consecutive intervals (symptoms to mammography, mammography to biopsy, biopsy to first treatment). Participants will complete a one-time questionnaire (up to 1 hour, with assistance if needed), and clinical data will be extracted in a standardized way from medical records (key dates and tumor characteristics). A random sample of 10% of incident breast cancer cases identified by each hospital information department will be used to ensure balanced geographic representation across 38 centers. The study will also explore how individual and contextual factors (psychological, behavioral, socio-demographic, access to care, communication) are associated with each time interval, and exploratory analyses will assess links with severity (metastases and prognostic score).

Inclusion Criteria:

• Female, age ≥ 18 years.
• Confirmed invasive breast carcinoma.
• Diagnosis in 2024 (and/or < 12 months at inclusion depending on center organization).
• Affiliated with the French social security system.
• Resident of Hauts-de-France since diagnosis.
• Information provided and non-opposition documented (MR-003).

Exclusion Criteria:

• Male breast cancer.
• Other histologies (phyllodes tumor, sarcoma, lymphoma).
• Pure ductal carcinoma in situ (in situ only).
• Personal history of breast cancer (including in situ).
• Non-French-speaking.
• Person deprived of liberty.

Adult women with recently diagnosed invasive breast carcinoma, receiving care in a participating Hauts-de-France center.