Intensity-modulated radiotherapy (IMRT) has become the standard radiotherapy technology utilized for the treatment of prostate cancer, as it permits the delivery of highly conformal radiation dose distributions. Image-guided radiotherapy (IGRT) is an essential companion to IMRT that allows the treatment team to account for daily changes in target anatomy and positioning. In the present review, we will discuss the different sources of geometric uncertainty and review the rationale behind using IGRT in the treatment of prostate cancer. We will then describe commonly employed IGRT techniques and review their benefits and drawbacks. Additionally, we will review the evidence suggesting a potential clinical benefit to utilizing IGRT.
Keywords: Calypso 4D; Prostate cancer; ViewRay; cine magnetic resonance imaging (cine MRI); cone beam computed tomography (CBCT); electromagnetic transponders; image-guided radiotherapy technology (IGRT); intensity-modulated radiation therapy (IMRT); intraprostatic fiducial markers (FM); magnetic resonance imaging-guidance (MRI-guidance); stereoscopic X-ray imaging; stereotactic body radiotherapy (SBRT); ultrasound (US).