Combinatorial ablation and immunotherapy
Combinatorial ablation and immunotherapy is an oncological treatment that combines various tumor-ablation techniques with immunotherapy treatment. Combining ablation therapy of tumors with immunotherapy enhances the immunostimulating response and has synergistic effects for curative metastatic cancer treatment. Various ablative techniques are utilized including cryoablation, radiofrequency ablation, laser ablation, photodynamic ablation, stereotactic radiation therapy, alpha-emitting radiation therapy, hyperthermia therapy, HIFU. Thus, combinatorial ablation of tumors and immunotherapy is a way of achieving an autologous, in-vivo tumor lysate vaccine and treating metastatic disease. Mechanism of action. Take magnetic hyperthermia for example. By applying magnetic nanoparticle-mediated  hyperthermia with a threshold of 43 °C in order not to damage surrounding normal tissues, a significant quantity of heat-shock proteins (HSP) is expressed within and around the tumor tissues, inducing tumor-specific immune responses. In vivo experiments have indicated that magnetic nanoparticle-mediated hyperthermia can induce the regression of not only a local tumor tissue exposed to heat, but also distant metastatic tumors unexposed to heat. Partially or entirely ablating primary or secondary metastatic tumors induces necrosis of tumor cells, resulting in the release of antigens and presentation of antigens to the immune system. The released tumor  antigens help activate anti-tumor T cells, which can destroy remaining malignant cells in local and distant tumors. Combining immunotherapy (ie: checkpoint inhibitors, CAR-T cell therapy) and vaccine adjuvants (ie: interferon, saponin) with ablation synergizes the immune reaction, and can treat metastatic disease with curative intent. Ablation therapies. Various local ablation therapies exist to induce necrosis of tumor cells and release tumor antigens to stimulate an immunological response. These ablation therapies can be combined with a systemic immunotherapy: