IL4 and posterior cortical atrophy: Cytokines play an important role in the development of therapy resistance.52, 53 Current therapies such as radiation and docetaxel can trigger an inflammatory response, and an increase in cytokine levels of IL-6, IL-8 and IL-4 have all been reported.15, 20, 29, 54, 55In vitro studies demonstrated that, in cell lines, IL-4 enhances the DNA repair activity triggered by radiation therapy.56 In this study, we observed that IL-4 had no influence on clonogenic recovery of primary PCa cells following irradiation.