Fractionated Stereotactic Radiotherapy for Choroidal Melanoma

立體定位寡分次光子放射治療對脈絡膜黑色素瘤之結果分析

高偉恆(Wei-Heng Kao) ； 洪志宏(Ji-Hong Hong) ； 趙安年(An-Ning Chao) ； 王俊傑(Chun-Chieh Wang)

《放射治療與腫瘤學》 21卷3期 (2014/09) Pp. 191-199

https://doi.org/10.6316/TRO/201421(3)191

摘要

目標：雖然脈絡膜黑色素瘤是最常見的眼睛原發惡性腫瘤，但是在台灣仍是較為罕見的疾病。在本研究中，我們希望能夠了解使用立體定位寡分次光子放射治療對於此疾病的治療效果。材料與方法：從2009到2012年，共有6位脈絡膜黑色素瘤的病患拒絕接受眼球摘除手術並且使用直線加速器接受立體定位放射線體外照射治療。總劑量為50 Gy並分為5次進行。所有的病患於放射治療前以及治療後追蹤皆需要接受眼科詳細的檢查，包括：視力以及眼底鏡檢查。此外，電腦斷層也會在治療後用於追蹤腫瘤的治療效果反應。結果：在本研究中，一共三位病患有中型的腫瘤，另外三位擁有大型的腫瘤。腫瘤高度的中位數為9.3 mm，底部直徑中位數為13.4 mm，以及體積中位數為0.94立方公分。追蹤時間中位數為29個月，三年的局部控制、遠端轉移控制以及整體存活率皆為100%。有一位病患在接受治療的25個月後，因為治療後產生的新生血管型青光眼而接受眼球摘除手術。在四位治療前視力大於0.1的病患中，有三位仍然能夠在治療後保留視力。其中有一位34歲的病患於接受治療24個月後，發生了白內障的情況影響視力，並且在接受了人工水晶體置換手術後恢復了部分的視力。結論：此研究顯示總劑量為50 Gy分為5次的立體定位寡分次光子放射線治療對於脈絡膜黑色素瘤有著良好的局部控制率。保留視力以及減少放射治療引起的新生血管型青光眼是我們仍舊需要在未來努力的目標。

關鍵字

立體定位放射治療 ； 脈絡膜黑色素瘤 ； 視力保留

並列摘要

Purpose/Objectives: Although choroidal melanoma is a relatively rare disease in Taiwan, this study aimed to investigate the feasibility of using linear accelerator based hypofractionated stereotactic radiotherapy (SRT) for choroidal melanoma. Materials and Methods: From 2009 to 2012, 6 patients with choroidal melanoma were treated for a total dose of 50 Gy in 5 fractions with SRT. All patients underwent image studies (CT or MRI) and ophthalmologic examination, including visual acuity, funduscopy and ultrasound, before and regularly after treatment. In this study, three patients had medium-sized tumors (tumor height ≤ 10 mm and tumor base ≤ 16 mm) and the other three had large-sized tumors (tumor height ＞10 mm or tumor base ＞16 mm). Results: With a median follow-up duration of 29 months, the 3-year local control, distant metastasis free and overall survival were all 100%. One patient had enucleation due to the development of radiation-induced neovascular glaucoma after 25 months. In addition, one patient developed a cataract after 24 months and received an intraocular lens implant. Among the four patients with pre-treatment visual acuity ＞0.1(VA), VA was preserved in 3 patients. Conclusions: Our study supports the theory that hypofractionated SRT with 50Gy applied in five fractions seems to be sufficient to obtain good tumor control. More efforts should be made to reduce the radiation-induced neovascular glaucoma and preserve visual acuity.

並列關鍵字

Choroidal melanoma ； Stereotactic radiotherapy ； Visual acuity preservation