Étude épidémiologique des facteurs de risque et des caractéristiques cliniques des cancers du sein HER2- positif

Abstract

Breast cancer represents, in Algeria as in many other countries, the leading cause of cancer among women. Among its molecular subtypes, HER2-positive breast cancer stands out due to its biological aggressiveness and therapeutic particularities. In this retrospective study, we analyzed the clinical, epidemiological, and histopathological data of 50 patients diagnosed with HER2-positive breast cancer between 2022 and 2024 at the oncology department of Dr. Benzerdjeb Hospital in Ain Temouchent.The results reveal that the majority of patients were aged between 45 and 60, with a predominance of left breast involvement (50%). Histological analysis showed a clear predominance of invasive ductal carcinoma (77%) and SBR grade II (72.41%).Regarding risk factors, most patients were married, multiparous, and had experienced a first pregnancy before the age of 25. Furthermore, around 30% had a history of benign breast conditions, and 50% reported a family history of breast cancer.The upper outer quadrant was the most common tumor location (52.94%). TNM classification highlighted a significant proportion of T2 tumors and lymph node involvement classified as N1 in 46% of cases.Hormone receptors (ER and PR) showed co-expression in 75% of the cases, and the Ki67 index was elevated in over a third of the patients, indicating high proliferative activity. From a therapeutic perspective, although surgical information was incomplete in many records, chemotherapy combined with anti-HER2 targeted therapies—particularly trastuzumab—was the mainstay of treatment. These therapies were prepared under controlled conditions in the chemotherapy unit following strict protocols.This study highlights the specific characteristics of HER2-positive breast cancer in a regional context, while underscoring the importance of early screening, molecular stratification, and access to targeted therapies to improve patient prognosis.