Metastasis patterns in patients with HER2-positive breast cancer

Objective. The purpose of this research is to analyze treatment outcome and evaluate metastasis patterns in patients with HER2-positive breast cancer. Materials and Methods. The trial enrolled 254 women with HER2-positive breast cancer. All of them received integrated treatment at Ulyanovsk Regional Clinical Oncology Center. To conduct comparative analysis, patients were divided into two groups: those receiving and not receiving targeted therapy in the adjuvant regimes. In each group, we analyzed metastasis patterns and assessed overall and disease-free survival in this category of patients. Results. The analysis showed that in the group of patients who received trastuzumab targeted therapy, the incidence of loco-regional recurrence was higher and amounted to 17 cases (11,33 %) compared with 3 cases (2,88 %) observed in the group who did not receive targeted therapy. Besides, the amount of visceral metastases in the first group was lower than in the second one (10,67 vs 14,43 %). The results indicate that use of trastuzumab in the adjuvant regimes reduces the frequency of visceral metastases, which are the main mortality factors in this patient population. Conclusions. The use of trastuzumab-based targeted therapy improves overall survival, but does not modify the disease-free survival of patients with HER2-positive breast cancer.