Exploring Therapeutic Challenges in Patients with HER2-Positive Breast Cancer-A Single-Center Experience.

Breast cancer is one of the most common forms of neoplasia worldwide. The purpose of our observational study was to evaluate the status of HER2 overexpression among new cases of breast neoplasia with an impact on the natural history of breast cancer disease and therapeutic personalization according to staging. This study included 45 breast cancer patients which have an overexpression of HER2 through the mutation of the EGFR-ERBB2 receptor. Immunohistochemical staining was performed on sections of formalin-fixed paraffin-embedded breast tissue. The patients were evaluated demographically and therapeutically in all stages. The post-surgical histopathological examination revealed complete pathological responses in 19 patients and pathological responses with residual disease either at the tumor level or lymphatic or both variants in a percentage of 44% (15 cases). The disease-free interval (DFI) under anti-HER2 therapy was recorded in 41 patients, representing 91% of the study group. Anti-HER2 therapy in any therapeutic stage has shown increased efficiency in blocking these tyrosine kinase receptors, evidenced by the high percentage of complete pathological responses, as well as the considerable percentage (47%) of complete remissions and stationary disease, in relation to the HER2-positive patient group.