IBC is characterized by a rapid onset, redness and swelling of the breast. Despite an aggressive therapy with chemotherapeutics, radiation and surgery the survival rate is the worst among all breast cancers with less than 40 % survival after 5 years. Therefore, further research is necessary. Although IBC and non-IBC (nIBC) tumours are different diseases in many ways, our lab showed that genetically an IBC tumour and a nIBC tumour are not so different after all. Based on these findings we think that the non-cancerous cells that are part of the tumour or the patient's response to the tumour can explain the difference. Thus we are interested in how the surrounding tissue and especially the immune cells respond to IBC and how this is different from nIBC. To examine this we will start our research by determining what types of cells are present in both tumour types and whether they are functioning as they should be. By correlating the presence of certain cell types or functional markers with response to treatment, survival information and properties of the tumour we can see what type of cells or functional markers could predict prognosis or response to therapy and can be called biomarkers. Furthermore, the combination of this information with data about which genes in a tumour sample are over- or underexpressed could lead to a better understanding of the genetic pathways that are important in IBC growth. If we can alter these pathways, we might find new targets for therapy.