Trastuzumab som adjuvant behandling avbröstcancerpatienter med HER2-positivitet
Hur effektivt är det?
Breast cancer is the most common tumor disease among women in Sweden. About 7000persons, having a median age of 65, are diagnosed each year with this disease. Withmammography screening, breast cancer can be detected in an early stage which improves theoverall survival (OS). 20-30 % of the breast cancer tumors are overexpressing humanepidermal growth factor receptor 2 (HER2), which is a protein that stimulates cell proliferation.Trastuzumab (Herceptin®) is a humanised monoclonal antibody that targets the HER2-proteinand prevent the signals for cell proliferation.Trastuzumab has earlier been used for treatment of metastatic breast cancer. In the year of 2007trastuzumab was approved for adjuvant treatment of patients who has been medicated withsurgery and/or radiation.The aim of this study was to investigate the effects of adjuvant treatment with trastuzumab inHER2-positive breast cancer patients. The method was a literature study based on scientificarticles identified from the database PubMed.The articles that were choosen were two meta-analysis and three cohort studies. The benefitsand effects of trastuzumab administration on patients with HER2-positive breast cancer weredescribed in these articles. Primary endpoint was disease-free survival (DFS). All articlesshowed that the DFS increased in breast cancer patients treated with adjuvant trastuzumab but alonger follow-up of four years, showed a reduction of both DFS and OS.The conclusion of this study was that trastuzumab as adjuvant treatment is favorable and shouldbe considered as treatment of breast cancer with HER2 overexpression that has been analyzedby immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH).