Radiation treatment for cancer is very effective in killing cancer cells and often used as adjuvant therapy post-surgery.

Toxicity may be acute (burnt skin, cough, pains) but can also present years later as a progressive condition called radiation fibrosis syndrome (RFS). 

RFS can affect any tissue type, including the skin, ligament, tendon, muscles, viscera, nerve, as well as lungs, the gastrointestinal and genitourinary tracts, bone, or other organs, depending upon the treatment site.