HER2positiva
HER2-positiva describes tumors that overexpress the human epidermal growth factor receptor 2 (HER2) due to amplification of the ERBB2 gene. In breast cancer, HER2-positive tumors comprise about 15–20% of cases and are typically more aggressive than HER2-negative tumors. HER2 overexpression can also occur in gastric and gastroesophageal junction cancers and, less commonly, in other tumor types.
Diagnosis is based on tumor testing. Immunohistochemistry (IHC) assesses HER2 protein levels, with a score of
Clinical implications and treatment rely on this biomarker. In early-stage disease, treatment often combines anti-HER2 therapy
Monitoring and safety are important. Cardiotoxicity is a known risk with HER2-targeted therapies, so cardiac function