title: Organ motion in image-guided radiotherapy: lessons from real-time tumor-tracking radiotherapy.
abstract: External radiotherapy using imaging technology for patient setup is often called image-guided radiotherapy (IGRT). The most important problem to solve in IGRT is organ motion. Four-dimensional radiotherapy (4DRT), in which the accuracy of localization is improved - not only in space but also in time - in comparison to 3DRT, is required in IGRT. Real-time tumor-tracking radiotherapy (RTRT) has been shown to be feasible for performing 4DRT with the aid of a fiducial marker near the tumor. Lung, liver, prostate, spinal/paraspinal, gynecological, head and neck, esophagus, and pancreas tumors are now ready for dose escalation studies using RTRT.
authors: Division of Radiation Oncology, Department of Radiology, Hokkaido University School of Medicine, North-15 West-7, Kita-ku, 060-8638 Sapporo, Japan. hshirato@radi.med.hokudai.ac.jp
authors: Hiroki
authors: H
authors: Shirato
authors: Shinichi
authors: S
authors: Shimizu
authors: Kei
authors: K
authors: Kitamura
authors: Rikiya
authors: R
authors: Onimaru
mesh_terms: D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000145:classification / Q000379:methods; D007564:Japan; D009369:Neoplasms / Q000532:radiotherapy; D011881:Radiotherapy, Computer-Assisted / Q000145:classification / Q000379:methods