Image-guided radiotherapy for prostate cancer by CT–linear accelerator combination: Prostate movements and dosimetric considerations

Use of Implanted Markers and Interportal Adjustment With Real-Time Tracking Radiotherapy System to Reduce Intrafraction Prostate Motion

“…Recent studies have shown that ultrasound-based systems, in-room CT, in-room kV fluoroscopy, and CBCT (cone beam computed tomography) are useful in reducing the set-up error for a majority of radiation patients (17,18,19,20). Our method using fiducial markers and two sets of fluoroscopy was also shown to be useful to reduce set-up error compared to the skin-based setting (5,13,15).…”

Stereotactic Body Radiotherapy for Pancreatic Adenocarcinoma: Set-Up Error Correction Using Internal Markers and It’s Association with the Patient’s Body Mass Index

“…Image-guided respiratory-gated radiation therapy has been a major advancement in minimizing inter-and intra-fractional target variations. To minimize and correct for setup uncertainties and inter-fractional motion of extracranial tumors, various immobilization and localization techniques have been clinically implemented, including transabdominal ultrasonography (Lattanzi et al 1999;Chandra et al 2003;Langen et al 2003), megavoltage imaging (Schiffner et al 2007;Serago et al 2006), kilovoltage imaging (Jaffray et al 1999;Kupelian et al 2008), use of an in-room computed tomography (CT)-linear accelerator system (Court et al 2003;Wong et al 2005), cone-beam CT (Jaffray et al 1999;Kupelian et al 2008), and placement of internal fiducials (Kupelian et al 2008;Chen et al 2007;Chung et al 2004). Pancreatic tumor targets usually exhibit inter-fractional motion relative to the bony anatomy because of daily variation in stomach and duodenal filling and respiratory patterns.…”

Single session robotic radiosurgery for a patient with low risk prostate cancer

“…Hypofractionated stereotactic treatment is suggested to reduce the volume of adjacent tissue receiving high dose radiation and to apply a much larger, ablative dose of radiation per treatment fraction. Prostate movement prevents the application of radiosurgery by conventional radiation systems as the prostate can move up to 1.5 in every direction during treatment delivery [6][7]. To compensate the effects of prostate movement, a larger radiotherapy planning target volume is usually used.…”