In order to stick preferentially to tumor tissue, don’t these beads need a surface coated with a “cancer specific” tag of some sort?? I don’t see how the selectivity exists, otherwise.
I don't understand this technique other than they're using ultrasound to localize the tumors. That probably 10 - 20 percent of the cost of MRI images.
You can register for free access to the original paper. I'm not giving them all sorts of personal info.