ABSTRACT
Radiation therapy for lung cancer has a unique set of requirements because of the anatomy in the thorax. First of all, lung is a very radiosensitive organ and exhibits a greater effect of volume dependency than other organs. Thus, designing effective radiation beams that can reach tumors surrounded by a large amount of normal pulmonary tissue has been a great challenge in radiation oncology. Second, in the normal thorax, critical structures such as the mediastinum, heart, esophagus, and spinal cord are often very close or adjacent to tumors. Thus the risk of developing potentially fatal toxicity in these normal structures poses a great concern for oncologists treating lung cancers. Often, normal tissue complication is a major impediment to dose escalation and further improvements in therapeutic efficacy. Treatment strategies must effectively address improving tumor control without significantly increasing toxicity and compromising quality of life in patients with lung cancers.
