Immunotherapy and Radiation Therapy in Renal Cell Carcinoma

Background: The management of renal cell carcinoma is rapidly evolving and immunotherapy, mostly consisting of immune checkpoint inhibitors, is revolutionizing the treatment scenario of metastatic patients. Novel fractionation schedules of radiotherapy, consisting of high doses in few fractions, can overcome the radioresistance of this tumor. Localized radiotherapy is associated with a systemic effect, known as the abscopal effect. This effect mediated by the immune system can be enhanced associating radiotherapy with immunotherapy. Objective: In this review, we explore the role of radiotherapy and immunotherapy in RCC, the rationale of combining these strategies and the on-going clinical trials investigating combinations of these two treatment modalities. Conclusion: Combining immunotherapy and radiotherapy has a strong rationale and pre-clinical studies support their association because it can overcome the immunosuppression of the tumor microenvironment and increase the anti-tumor immune response. More clinical evidence, deriving from onclinical trials, are needed to prove the efficacy and safety of these treatments combined.