Vol 7, No 4 (2011)
Review paper
Published online: 2011-10-26
The therapy interfering EGFR activation in breast cancer patients
Onkol. Prak. Klin 2011;7(4):159-176.
Abstract
HER2 receptor overexpression is present in about 20% of breast cancer patients and is associated with
aggressive course of the disease and shortening of disease-free and overall survival. Simultaneously,
overexpression of this receptor or HER2 gene amplification is a predictive factor for treatment with trastuzumab.
Trastuzumab is a monoclonal antibody directed against extracellular domain of HER2 receptor.
Trastuzumab binding with this receptor on the cancer cell’s surface results in an inhibition of intracellular
signaling pathway associated with HER2 receptor. It has been shown that trastuzumab in combination with chemotherapy significantly improved response rate and prolonged overall survival of advanced
HER2-positive breast cancer patients, compared to patients treated exclusively with chemotherapy. Moreover,
addition of trastuzumab to neoadjuvant chemotherapy leads to pathological complete remission
in a significant proportion of HER2-positive locally advanced breast cancer patients. Furthermore, use of
trastuzumab in combination with adjuvant chemotherapy in HER2-positive early breast cancer patients
was associated with about 50% reduction of risk of disease recurrence and about 30% decrease in
the risk of death. Most importantly, introduction of trastuzumab into clinical practice has opened a new
avenue of research focused on targeted therapy directed against molecular targets located in cancer
cell. Since than, intracellular signaling pathway associated with HER2 receptor has been the subject of
thousands of experimental and clinical studies. The ultimate aim of these studies is a steady improvement
in treatment results and prolongation of survival of patients suffering from this aggressive form of breast
cancer. As a result, introduction into clinical practice of new drugs that are active in the treatment of trastuzumab-
refractory patients is anticipated in the near future. A plethora of new drugs are at various stages
of clinical development at that moment. In this paper we present a review of data that were obtained in
controlled clinical trials in recent years, regarding the most important aspects of therapies interfering with
HER2 receptor in HER2-positive breast cancer patients.
Onkol. Prak. Klin. 2011; 7, 4: 159–176
Onkol. Prak. Klin. 2011; 7, 4: 159–176
Keywords: HER2HER2-positive breast cancertargeted therapytrastuzumablapatinibpertuzumabneratinib