The dawn of "immune-revolution" in children: early experiences with checkpoint inhibitors in childhood malignancies.

Modern immunotherapy with checkpoint inhibitors has changed clinical practice of adult patients with advanced cancer. Blockade of CTLA-4 and PD-1 pathways have shown survival benefits in different diseases. In children, combination of surgery, radiotherapy and chemotherapy have improved survival rates of solid tumors. However, the outcomes for subsets of patients such as those with high-grade, refractory, or metastatic disease remain extremely poor. Currently, the treatment of these patients is almost exclusively based on standard chemotherapy. The significant proportion of pediatric cancers with high number of mutations and subsequent high expression of neoantigens, together with the potential prognostic role of the immunosuppressive checkpoint molecules (CTLA-4, PD-L1) can represent a promising rationale that support the use of checkpoint inhibitors. We made a revision about emerging data regarding safety and activity of checkpoint inhibitors in children with solid tumors.