Abstract:
Technological advances in MRI-guided radiation therapy (MRIgRT) have improved real-time visualization of the prostate and its surrounding structures over CT-guided radiation therapy. Seminal studies have demonstrated safe dose escalation achieved through ultrahypofractionation with MRIgRT due to planning target volume (PTV) margin reduction and treatment gating. On-table adaptation with MRI-based technologies can also incorporate real-time changes in target shape and volume and can reduce high doses of radiation to sensitive surrounding structures that may move into the treatment field. Ongoing clinical trials seek to refine ultrahypofractionated radiotherapy treatments for prostate cancer using MRIgRT. Though these studies have the potential to demonstrate improved biochemical control and reduced side effects, limitations concerning patient treatment times and operational workflows may preclude wide adoption of this technology outside of centers of excellence. In this review, we discuss the advantages and limitations of MRIgRT for prostate cancer, as well as clinical trials testing the efficacy and toxicity of ultrafractionation in patients with localized or post-prostatectomy recurrent prostate cancer.
摘要:
MRI引导放射治疗(MRIgRT)的技术进步改善了CT引导放射治疗的前列腺及其周围结构的实时可视化。精液研究表明,由于计划目标体积(PTV)边缘减少和治疗门控,通过MRIgRT的超小分割可实现安全的剂量增加。使用基于MRI的技术的桌上适应还可以结合目标形状和体积的实时变化,并且可以减少对可能进入治疗领域的敏感周围结构的高剂量辐射。正在进行的临床试验寻求使用MRIgRT改善前列腺癌的超小分割放射治疗。虽然这些研究有可能证明改善生化控制和减少副作用,有关患者治疗时间和操作工作流程的限制可能会妨碍在卓越中心之外广泛采用该技术。在这次审查中,我们讨论了MRIgRT治疗前列腺癌的优势和局限性,以及临床试验测试局部或前列腺切除术后复发性前列腺癌患者的疗效和毒性。