Ultrasound tumor ablation: immune effects and perspectives of integration in the modern treatment of advanced cancer

Despite significant progress in molecular oncology and immuno-oncology, only 20-30 % of patients with advanced cancer can be cured with modern treatments indicating that new approaches are needed. Further improvements in immunotherapy of cancer are associated with enhanced tumor immunogenicity, induction of inflammatory phenotype and inhibition of immune suppression at the tumor microenvironment level. In this context, high-intensity focused ultrasound (HIFU) ablation have several advantages, particularly it is able to elicits a rapid clinical and immune response, is non-invasive, have low local morbidity, allows repeated sonications, have relative low cost and does not require long hospitalization. In addition to cytoreduction and decreasing of systemic immune suppression, HIFU generates a tumor debris depot acting as vaccine in situ. Immunogenic cell death elicits a CD4+ and CD8+ cytotoxic T-cell response, but several regulatory mechanisms, particularly PD-1L expression, are promoted in response to enhanced immune cells infiltration of heated and distal tumors...