HDR Brachytherapy for Intraocular Melanoma

描述（由申请人提供）：HDR近距离治疗眼内黑色素瘤-项目摘要/摘要该I期项目的总体目标是开发一种治疗眼内黑色素瘤的近距离治疗系统，减少住院时间，提供改进的剂量测定以减少并发症，提高临床医生的安全性并降低成本。这将通过开发基于低能量伽马射线源169镱的改进的高剂量率近距离放射治疗系统来实现。这种发展将消除目前低剂量率治疗所需的长期住院治疗，并减少对外科医生和其他医院人员的辐射暴露。这也将获得更好的剂量优化的好处，其附带的治疗反应的改善，以及后负荷高剂量率临时近距离治疗源的潜在更好的治疗效果。我们进一步认为，这种放射性核素的特殊放射特性将导致比目前可用的放射性核素对巩膜的剂量减少，从而减少该手术的并发症。我们的目的是证明使用169镱的高剂量率近距离治疗可以是治疗这种癌症的有效方法。脉络膜黑色素瘤是最常见的原发性眼部恶性肿瘤，在美国每年约有1500例新病例报告。这些肿瘤既危及视力，又危及生命，根据肿瘤大小，由于全身转移，5年死亡率约为10%至30%。美国国家眼科研究所和国家癌症研究所赞助的眼部黑色素瘤合作研究（COMS）是一项前瞻性多中心临床试验，旨在判断近距离放疗与去核在死亡率方面的治疗效果，结果显示，在统计和实际意义上，近距离放疗的生存率与去核一样好。然而，目前含有125碘或103钯近距离治疗种子的眼斑必须留在原位5至12天，并且需要第二次手术将斑块从患者身上移除。125碘和103钯的低平均光子发射能量导致巩膜的高剂量，以便将所需剂量传递到肿瘤顶点。这导致了损伤和并发症的风险。使用169镱的高剂量率近距离放射治疗系统的开发可以实际和经济地实施，并将克服当前治疗方法的缺点，同时提供临床效益。HDR近距离治疗眼内黑色素瘤-项目描述高剂量率169镱近距离治疗的临床实施将使患者受益，因为它可以缩短某些类型眼癌的治疗时间，并可能减少并发症。这也将使执行该程序的医生更安全，并通过将患者的住院时间从一周减少到一天，使患者更舒适。这也会降低手术的成本。

DESCRIPTION (provided by applicant): HDR Brachytherapy for Intraocular Melanoma - Project Summary/Abstract The overall objective of this Phase I program is to develop a brachytherapy system for the treatment of intraocular melanoma that reduces hospitalization time, provides improved dosimetry to reduce complications, improves safety for the clinician and reduces cost. This will be achieved through the development of an improved high dose rate brachytherapy system based on the low- energy gamma ray source 169 Ytterbium. Such development would eliminate the long hospitalization required with the current low dose rate treatment and reduce the radiation exposure to the surgeon and other hospital personnel. This would also achieve the benefits of superior dose optimization with its collateral improvement in therapeutic response, along with potentially better treatment efficacy available with afterloaded high dose rate temporary brachytherapy sources. We further believe that the specific radiological properties of this radionuclide will result in reduced dose to the sclera than can be achieved with the currently-available radionuclides, and thereby will reduce the complications from this procedure. We aim to demonstrate that high dose rate brachytherapy using 169 Ytterbium can be an effective treatment method for this cancer. Choroidal melanoma is the most common primary ocular malignancy, with some 1500 new cases reported yearly in the United States. These tumors are both sight- and life-threatening, with approximately 10% to 30% five-year mortality rate owing to systemic metastasis, depending on tumor size. The National Eye Institute- and National Cancer Institute-sponsored Collaborative Ocular Melanoma Study (COMS), a prospective multicenter clinical trial to judge treatment efficacy brachytherapy v. enucleation in the context of mortality, showed that brachytherapy conveyed as good a survival rate as enucleation, in both a statistical and practical sense. However, current eye plaques, containing 125Iodine or 103Palladium brachytherapy seeds must be left in place from 5 to 12 days, and require a second surgery to remove the plaque from the patient. The low average photon emission energies from 125 Iodine and 103 Palladium result in a high dose to the sclera in order to deliver the desired dose to the apex of the tumor. This results in risk of damage and complications. The development of a high dose rate brachytherapy system using 169 Ytterbium can be practically and economically implemented and will overcome the shortcomings of the current treatment method while providing clinical benefit. HDR Brachytherapy for Intraocular Melanoma - Project Narrative The clinical implementation of high dose rate 169 Ytterbium brachytherapy will benefit patients by resulting in shorter treatment of certain types of eye cancer, and potentially fewer complications. This will also lead to greater safety to the physicians performing this procedure and greater comfort to the patients by reducing their hospital stay from a week to a day. It will also result in reduced cost for this procedure.