When they analysed the data 15 months after the start of the trial, the researchers found that there was no evidence of any cancer remaining in the breast in 41.3% of women with HER2-positive tumours who had received both chemotherapy and trastuzumab; whereas the pathologic complete response rate (pCR, complete disappearance of cancer cells from the breast) was 19.5% in women who had not received trastuzumab.
Prof Untch said: Previous studies have shown that HER2-positive women who do not receive trastuzumab never have a pCR rate that exceeds 20%. Our study has shown that it is possible to combine trastuzumab with anthracycline/taxane chemotherapy regimen without any significant adverse effects on the heart, thereby significantly increasing the pCR rates for these women to 41.3%.
The researchers are continuing to follow the women to see whether the pCR rates translate into improved overall survival. In addition, they have started a further trial, the GeparQuinto study, which will compare the combination of chemotherapy plus trastuzumab with lapatinib (a tyrosine kinase inhibitor) as a pre-operative treatment.
The GeparQuattro trial was run jointly in more then 100 breast cancer centres by the German Breast Group (GBG) and the Arbeitsgemeinschaft Gynkologische Onkologie (AGO), the two major German cooperative research groups for the treatment of gynaecological malignancies and breast cancer. Professor Gunter von Minckwitz, managing director of GBG, is the principal investigator for the study.
|Contact: Emma Mason|
ECCO-the European CanCer Organisation