Novel Delivery System for High Dose Rate Intensity Modulated Brachytherapy with Yb-169 as a Radiation Source

放射治疗是一种有效而安全的癌症治疗方法。大约50%的癌症患者从这种治疗中受益，也就是说，每年有近10万加拿大癌症患者受益。近距离放射治疗是放射治疗的一种形式，将放射源放置在肿瘤内部或**附近，使用短时间植入的细中空管(导管)，**给予肿瘤高剂量的辐射，同时保持对周围健康组织的低剂量。然而，传统的近距离放射治疗的剂量分布在所有方向都是相同的，导致剂量泄漏到对辐射敏感的**健康组织。这项提议旨在开发一种新型的辐射传输系统，它将**通过在植入的中空管中加入辐射屏蔽物来**操纵辐射剂量以符合肿瘤的形状，即该传输系统将调制从近距离治疗源发射的辐射的强度**。在治疗过程中，防护罩可以旋转，将辐射引向肿瘤，远离健康组织。开发和使**调强近距离放射治疗在临床上可用，将显著提高**近距离放射治疗的潜力，同时减少毒性，将提高加拿大前列腺癌、乳腺癌、宫颈癌、子宫癌、阴道癌、外阴癌、头颈癌和**食道癌的治愈率和生活质量**。此外，这项提议将提供本科生和研究生**在辐射肿瘤学、辐射物理学、生物学、**计算和工程学的多学科环境中工作。

Radiotherapy is an effective and safe treatment for cancer. Approximately 50% of cancer**patients benefit from this treatment, that is, close to 100,000 Canadians with cancer each**year. Brachytherapy, is a form of radiotherapy where radioactive sources are placed inside or**near the tumours using thin, hollow tubes (catheters) implanted for a short period of time,**giving a high radiation dose to the tumour while maintaining a low dose to surrounding healthy tissues. However, dose distribution in conventional brachytherapy is identical in all directions resulting in dose spillage to radiation sensitive**healthy tissues. This proposal aims to develop a novel radiation delivery system that will**manipulate the radiation dose to conform to the shape of a tumour by incorporating radiation**shields inside the implanted hollow tubes, i.e. the delivery system will modulate the intensity**of the emitted radiation from the brachytherapy source. The shields can rotate during the**treatment, direct the radiation towards the tumour and away from healthy tissues. Developing and making intensity**modulated brachytherapy clinically available, will significantly improve the potential of**brachytherapy with reduced toxicity will increase the cure rates and improve the quality of life**for Canadians with prostate, breast, cervical, uterine, vaginal, vulvar, head & neck and**oesophageal cancers. In addition, this proposal will offer undergraduate and graduate student**to work in a multidisciplinary environment with radiation oncology, radiation physics, biology,**computing and engineering.