Despite recent progress and therapeutic advances made in the field of breast cancer. This pathology remains the main cause of female cancer and repre-sents a real major public health problem in Algeria as well as globally. The objective of this study, carried out in the Algerian West, was to assess the epidemiological profile of breast cancer in the Oran region through the pa-tients recruited in the Regional Military Hospital of Oran University (HMRUO), then to determine the clinical, biological and pathological factors that conditioned the overall survival. Among the methodological approaches used in our study were classical histology, immunohistochemistry and fluo-rescence in situ hybridization (FISH) techniques of different biological mar-kers (HER2, hormone receptors (RE and RP). The analysis is carried out using the Epi Info software version 3.4 on all invasive cancers. In a retrospective study of 265 patients with breast cancer over 3 years (February 2017–October 2019), we examined the epidemiological profile of breast cancer to determine the impact of biological and prognostic factors on survival over 3 years. Invasive tumours were found in 95.5% of the women. The average tumour size was big [3.6 (SD 2.6) cm] and only 14% were histological grade I. Overall survival at 3 years was only 49% for the RE–/RP–/HER2– subtype and 75% for the RE–/RP–/HER2+ subtype, while it was 96% for the RE+/RP+/HER2– subtype. The young age, large tumour size and high histological grade in our population suggest a lack of awareness of women about breast can-cer.