硼中子捕獲治療於臺灣癌症放療發展策略研究

Abstract

自民國七零年代起，癌症即成為國人主要之致死原因，近年來，每年因癌病死亡之國人數已突破四萬人，國內外醫學界亦均以突破癌病治療為臨床及基礎研究之主要目標。放射治療的臨床運用甚早，至今已超過百年，在目前及預估未來癌病治療一重要角色，極具效益。其主要特色主要建立在原子科學的成熟發展，透過有效之放射線粒子作用，得以有效摧毀並破壞腫瘤細胞，因此很多結合放射線與腫瘤治療的概念應運而生，從早期普遍利用鈷六十所產生的加馬射線(gamma ray)，直到現今普遍利用直線加速器所產生之X-rays以及電子射束等，均提供臨床腫瘤治療一種穩定有效之腫瘤治療方式。然誠如很多腫瘤臨床醫療工作者的觀察，放射線治療並不全然是腫瘤治療的萬靈丹藥，仍有其限制，及待突破之處。主要因素除包含放射線本身物理條件之限制外，其主要亦包括腫瘤細胞本身對於放射射源之反應敏感程度，相較於放射敏感之腫瘤(如淋巴瘤lymphoma、生殖細胞瘤germinoma等)，很多具放射抗性之腫瘤(如黑色素細胞瘤melanoma，惡性腦瘤malignant glioma，惡性肉瘤sarcoma等)，對於傳統放射線射源(加馬線或X射線)腫瘤不會明顯消退，侷限了放射線治療的臨床效果。因此具有強大放射生物效應且較低正常組織傷害性的放射線射源，尤其是能專門針對腫瘤的 ”標靶放射治療 ”，成為現今放射腫瘤醫學熱門發展之目標。 舉凡現今國際知名之重粒子治療(heavy particle radiotherapy)及硼中子捕獲治療(boron neutron capture therapy; BNCT)等，均是建立在此治療概念及實務應用。透過結合較佳之輻射生物反應，以及精準之放射物理技術，可使此放射技術療法對特定的癌症提供較傳統放療有更佳之治療成效。亦可結合現有各類先進之癌症治療方法提供多元治療之選擇與結合，而有最佳之效益及突破。 本研究建立於目前癌症先進設備技術及逐漸進步的放射治療成果經驗，結合多年來國內唯一，世界上少數的硼中子捕獲治療的研究團隊，所共同完成此令人期待矚目的標靶放射治療臨床試驗研究。以此再進一步探討如何讓此極具發展潛力及效益的標靶放射治療，如何在未來更廣泛的使用。實務發展可設置於醫院的加速器型設備，其應用發展及可與各類治療結合應用推廣的發展策略，在未來是具創新突破性且可落實。本研究於國內立於先基，希此研究及初步成果能更激勵同儕於標靶放射治療研究努力，期對癌症治療有進一步之突破。

Since 1980s, cancer has become the principal cause of death in Taiwan. The mortality number is higher than 40,000 each year. Both clinical and basic cancer researchers worldwide are eager to overcome this intractable disease. Radiotherapy plays a very important role in cancer treatment for more than one hundred years. The most important characteristic of radiotherapy is that it destroys cancer cells via DNA damage. Therefore, a lot of new radiotherapy techniques, such as gamma-ray (generated by cobalt 60) and X-rays (generated by linear accelerator) had been developed, They all make stable and reliable contributions for cancer treatment. However, not every types of caner can be overcome entirely by conventional radiotherapy due to dismal response contributed by radioresistance. For some radiosensitive tumors, including lymphoma or germinoma, tumor bulk will disappear soon after radiotherapy. But for some tumors with poor radiosensitivity, such as melanoma in skin or glioblastoma in brain (malignant brain tumor), conventional radiotherapy only has little impact and cannot work efficiently. Therefore, if we can develop some new “targeted radiotherapy” which can provide higher radiation effectiveness with relatively less normal tissue toxicity, it’ll become the most popular goal for the modern radiotherapy development. Up to now, the most well-established heavy particle radiotherapies globally, such as Boron Neutron Capture Therapy (BNCT) and so on, are all based on the modern concepts and practical use. It can combine the excellent radiobiological effectiveness and precise radiation physical technique which can also make better clinical results in current cancer treatment. Therefore, we strongly believe that it will provide a new option and breakthrough for future cancer treatment with higher benefits. This research project is based on the clinical results of cancer treatment at Taipei Veterans General Hospital and National Tsing-Hua University using BNCT. Our group is one of the few teams in the world who are capable to conduct this state-of-the-art cancer treatment. We will take advantage of our encouraging results as well as experiences to further develop this promising therapy. In the foreseeable future, hospital-based BNCT will be available for widespread utilization of this treatment. Our efforts had laid the groundwork for future development of BNCT in Taiwan. We are hoping these initial results could give our fellow researchers confidence in continuing development of “Targeted Radiotherapy”, thereby bringing breakthrough to cancer treatment.