This study is a non-interventional (NIS), multicenter, retrospective cohort study, which will obtain data from patients diagnosed with invasive breast cancer between 2002 and 2005 in the medical oncology departments of hospitals that are members of GEICAM (using information obtained from patient medical histories).

There is no specific treatment regimen for this study. This is an observational retrospective study in which the clinical decisions concerning the optimal strategy in the treatment of the disease for each patient have been taken independently and prior to the physician's decision to include patient data in this registry, in keeping with the drug information, local treatment guidelines and/or standard clinical practice.

The study target population are all patients (men and women) who have been newly diagnosed with invasive breast cancer between January 1, 2002 and December 31, 2005 and treated in the medical oncology departments of participating sites, ensuring an approximate follow-up of 10 years.

Inclusion Criteria:

• Patients whose first primary breast invasive tumor diagnosis occurred between January 1, 2002 and December 31, 2005 and who have received treatment in the medical oncology departments of participating sites.
• Patients who were diagnosed at the participating site; otherwise the site where the initial diagnosis was made should be contacted with in order to confirm that the patient has not already been enrolled in the study or pending inclusion. The objective is to avoid duplicate records for displaced patients.

Exclusion Criteria:

• Patients with a single diagnosis of in situ carcinoma (without infiltrating component).

The study target population are all patients (men and women) who have been newly diagnosed with invasive breast cancer between January 1, 2002 and December 31, 2005 and treated in the medical oncology departments of participating sites, ensuring an approximate follow-up of 10 years.