Researchers from Moscow, in cooperation with the University of Washington have developed a method of designing therapeutic transducers that use nonlinear focused ultrasound for noninvasive ablation of tumors at deep tissue sites inside the body. The story at phys.org states:
"An international research team that includes physicists from Moscow State University (MSU) is studying the effect of high intensity focused ultrasound (HIFU) waves to destroy tumors inside the human body noninvasively, without surgical intervention. This therapeutic approach has been pursued for about 25 years; more recently, laboratory experiments are being translated to the clinic."
See the two methods used to solve the therapeutic issues with the full article at phys.org
h/t to phys.org