Lichen is the symbiotic association of a fungus (the mycobiont, which provides shelter and structure for the partnership or symbiosis), with an alga or cyanobacterium (the phoâ¦tobiont, also known as the phycobiont, which provides the food for the partnership from photosynthesis).
Some radiation therapy delivery methods include: 1  External beam radiation therapy â radiation is directed from a machine outside the body onto cancerous cells within the body.  Internal radiation therapy â radioactive material is placed (via a catheter or other carrier) directly into or near a tumor.
For more information about radiation, please visit RadiologyInfo. Radiation therapy uses high energy x-rays (photons) or particle beam (protons) to kill, shrink, control the growth of tumors, manage pain or to prevent cancer from spreading to other organs. Image Guided Radiation Therapy (IGRT): Uses imaging such as CT, MRI or PET during the treatment process. 2  This can result in more accuracy in photon radiation delivery and monitoring of treatment progress. 3  Particle beam (proton) therapy is also a used to treat tumors in the lung.