Short ReviewImmunotherapy targeting immune check-point(s) in brain metastases

- Immunotherapy with immuno-modulatory antibodies is showing a significant clinical impact in several human tumors of different histotype.
- Treatment of brain metastases and brain primary tumors remains an high unmeet medical need, and the efficacy of immunotherapy in these clinical setting remains to be largely demonstrated.
- Recent evidences support the activity of Immunotherapy with monoclonal antibodies (mAb) directed to different immune check-point(s) also in this clinical setting.
- We report recent results and ongoing clinical trials on immunotherapeutic approaches to brain metastases and primary brain tumors.

Immunotherapy with monoclonal antibodies (mAb) directed to different immune check-point(s) is showing a significant clinical impact in a growing number of human tumors of different histotype, both in terms of disease response and long-term survival patients. In this rapidly changing scenario, treatment of brain metastases remains an high unmeet medical need, and the efficacy of immunotherapy in these highly dismal clinical setting remains to be largely demonstrated. Nevertheless, up-coming observations are beginning to suggest a clinical potential of cancer immunotherapy also in brain metastases, regardless the underlying tumor histotype. These observations remain to be validated in larger clinical trials eventually designed also to address the efficacy of therapeutic mAb to immune check-point(s) within multimodality therapies for brain metastases. Noteworthy, the initial proofs of efficacy on immunotherapy in central nervous system metastases are already fostering clinical trials investigating its therapeutic potential also in primary brain tumors. We here review ongoing immunotherapeutic approaches to brain metastases and primary brain tumors, and the foreseeable strategies to overcome their main biologic hurdles and clinical challenges.