I'm impressed at how precisely and locally targeted the therapy seems to be. Many of the cancer immunotherapies I've heard about are systemic and risk overenga

I'm impressed at how precisely and locally targeted the therapy seems to be. Many of the cancer immunotherapies I've heard about are systemic and risk overengaging a diffuse immune response against multiple tissues. This approach trains in-situ using strong signatures from individual tumors first, before the antigens spread out across the body. Perhaps this localizes the cancer antigen signature better, so antibodies cause less collateral damage? But CAR-T therapy should do something similar, though re-introduction of the antibodies is systemic (untargeted). Is the administration of this therapy directly into the tumor somehow essential to its specificity?