Cancer du sein chez la jeune femme de l’ouest Algérien

Abstract

Breast cancer Is the Most Common neoplasm in women and represents a major public Health issue du to its high incidence and biological heterogeneity. It is a multifactorial disease resulting from the progressive accumulation of genetic and epigenetic alterations leading to the malignant transformation of mammary epithelial cells. This study highlights the main mechanisms involved in breast carcinogenesis, integrating histopathological (WHO), clinical (TNM), immunohistochemical (ER, PR, HER2, Ki-67), and molecular classifications. The analysis of intrinsic subtypes (luminal A, luminal B, HER2-enriched, and basal-like/triple-negative) emphasizes the importance of tumor heterogeneity in prognosis and therapeutic response. The involvement of the BRCA1, BRCA2, and TP53 genes is also addressed, highlighting their central role in DNA repair, cell cycle control, and genomic stability. Their alteration significantly contributes to chromosomal instability and the emergence of aggressive tumor phenotypes. Furthermore, HER2 (ERBB2) receptor overexpression is associated with constitutive activation of proliferative signaling pathways, influencing clinical outcomes and paving the way for targeted therapies that have significantly improved patient prognosis. Finally, particular attention is given to breast cancer in young women (<40 years), characterized by increased aggressiveness, often delayed diagnosis, and a higher proportion of unfavorable subtypes, requiring a multidisciplinary and personalized management approach.