Cancer research is becoming more and more specific as science advances. The general chemotherapy, radiation and surgery is slowly developing into more precise techniques for individual types and cases of cancer. Theraspheres are one example; used to treat certain types of liver cancer. This technique uses glass beads smaller than the diameter of a human hair to deliver radiation directly to the tumor. Because of the size difference in the blood vessels of the tumor, the radiation is localized and little to no harm is done to the surrounding tissues.
This technique could have huge implications if adapted for various other types of cancer.

http://livercancercenter.upmc.com/AdvancedApproaches/TherasphereBasic.asp?section=AdvancedApproaches

(Be sure to look at the link to the CT scans on this page too)