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 cannot consent that my mortal body shall be laid in a repository prepared for an Emperor or a King—my republican feelings and principles forbid it—the simplicity of our system of government forbids it.”
—Andrew Jackson (1767–1845)
“My country is bleeding, my people are perishing around me. But I feel as a South Carolinian, I am bound to tell the North, go on! go on! Never falter, never abandon the principles which you have adopted.”
—Angelina Grimké (1805–1879)
“Every political system is an accumulation of habits, customs, prejudices, and principles that have survived a long process of trial and error and of ceaseless response to changing circumstances. If the system works well on the whole, it is a lucky accident—the luckiest, indeed, that can befall a society.”
—Edward C. Banfield (b. 1916)