Association of Adjuvant Radiotherapy of Non-metastatic Breast Carcinoma With Immunomodulation and Circulating Tumor Cell Phenotype in Relation to Patient Age.

In a prospective study, the influence of adjuvant radiotherapy in patients with non-metastatic breast carcinoma on the epithelial tumor cells (CETCs) circulating in the blood and their immunohistochemical characteristics depending on age will be investigated. In addition to a histopathological assignment of the CETCs as cells of the primary tumor, major trigger points of the immune system will be exploratively analyzed. For this purpose, blood samples are taken from the patients at different time points after tumor resection and during adjuvant radiotherapy. In addition to the detection, isolation and genetic characterization of the CETCs, the determination of immunological biomarkers by immunophenotyping, among other methods, is planned. Furthermore, analyses of tissue from the primary tumor with respect to immunohistochemical features as well as tumor-infiltrating lymphocytes (TILs) are planned. The results will be classified and correlated especially with regard to patient age. As there are insufficient data available for breast carcinoma regarding radiotherapeutic effects on the immune system depending on patient age, it is of great interest to better understand these molecular biological basics in order to identify potential prognostic biomarkers.