Principles
Radiation therapy is used to kill cancer cells; however, normal cells are also damaged in the process. Currently, therapeutic doses of radiation can be targeted to tumors with great accuracy using linear accelerators (see radiation oncology); however, the normal liver tissue is very sensitive to external beam radiotherapy. Fortunately, malignancies (including primary and metastatic liver cancers) are often hypervascular; tumor blood supplies are often increased compared to those of normal tissue. Furthermore, the liver has a dual blood supply, receiving blood from both the hepatic artery and the portal vein. Hepatic malignancies derive most of their blood supply from the hepatic artery; whereas the normal liver derives most of its blood supply from the portal vein. Therefore, delivery of radioembolic particles through the branch of the hepatic artery supplying a tumor will preferentially lead to deposition of the particles in the tumor, while sparing normal liver from harmful side effects.
Read more about this topic: Selective Internal Radiation Therapy
Famous quotes containing the word principles:
“I have ever deemed it fundamental for the United States never to take active part in the quarrels of Europe. Their political interests are entirely distinct from ours. Their mutual jealousies, their balance of power, their complicated alliances, their forms and principles of government, are all foreign to us. They are nations of eternal war.”
—Thomas Jefferson (1743–1826)
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—Gerald R. Ford (b. 1913)