乳癌強度調控放射治療之表面劑量測量

Surface dose measurement for breast cancer by intensity modulated radiation therapy

陳麗萍(Li-Ping Chen)

指導教授 ： 陳信雄

中臺科技大學/健康科學院/放射科學研究所/碩士(2009年)

摘要

中文摘要

乳癌的放射治療是臨床上常用的一種輔助治療方式，有些乳癌患者在接受治療療程後期或是接受放射治療後的門診追蹤中，會發現在治療區域中的皮膚表面有明顯的皮膚效應產生。為了評估乳癌患者在接受強度調控放射治療(Intensity Modulation Radiation Therapy, IMRT)時其表面所接受到的劑量，本實驗將針對乳癌使用強度調控放射治療技術之明顯皮膚效應的區域，利用聚合膠片(Gafchromic EBT film)及兩種不同厚度的熱發光劑量計(Thermoluminescent dosimeter, TLD)在擬人假體(Rando-Phantom)上量測皮膚表面之劑量。乳癌強度調控放射治療計畫製作的條件為使用ELEKTA直線加速器的 6 MV光子能量，其每次治療的處方劑量為180 cGy，劑量率為300 MU/min。為準確評估乳癌病患在接受放射治療時的表面劑量，聚合膠片必須藉由統計的方法進行劑量校正，而熱發光劑量計也必須藉由統計的方法進行篩選及校正，以確保聚合膠片及熱發光劑量計在接受輻射劑量測量時的準確性。本實驗並進一步分析聚合膠片及熱發光劑量計兩種不同工具所量測到的吸收劑量的差異，以作為臨床治療計畫之參考價值。

關鍵字： 強度調控放射治療、聚合膠片、熱發光劑量計、表面劑量。

關鍵字

強度調控放射治療 ； 聚合膠片 ； 熱發光劑量計 ； 表面劑量

並列摘要

Abstract

The radiotherapy is a common auxiliary method for breast cancer treatment. Some breast cancer patients will show the obvious skin effect in the treatment area in later period of treatment course or after accepting the treatment. In order to evaluate the surface dose in the skin area when patient accepts the intensity modulation radiation therapy for breast cancer treatment. In this study, we measured surface dose with the Gafchromic EBT film and with two different thickness thermoluminescent dosimeters in the Rando-Phantom. The intensity modulation radiation therapy technique in this study was delivered with 6 MV and the prescribed dose was 180 cGy. To evaluate the surface dose accurately, the Gafchromic EBT film must be calibrate with statistical method. The thermoluminescent dosimeters were calibrated and selected with statistical method. Based on statistical calibration method, we can assure the accuracy in dose measurement with Gafchromic EBT film and thermoluminescent dosimeters. In this study, we also analyzed the different results of dose measurement between Gafchromic EBT film and thermoluminescent dosimeters. The results for our study could be a valuable reference for clinical application.

Keywords: Intensity Modulation Radiation Therapy, Gafchromic EBT film, thermoluminescent dosimeter, surface dose

並列關鍵字

Intensity Modulation Radiation Therapy ； thermoluminescent dosimeter ； Gafchromic EBT film ； surface dose

參考文獻

8.劉國基, 強度調控放射治療之表面劑量測量, 中臺科技大學放射科學研究所, 2006.

29.林廣軒, 強度調控放射治療體內底片劑量品質保證, 中臺科技大學放射科學研究所, 2006

25.董尚倫,羅濟慶,葉砡秀,張國華,陳弘政,李俊信,低輻射劑量下TLD-100H 之校正與線性測試,放射治療與腫瘤學雜誌, 4: 215-221,1997.

2.Kestin LL, Sharpe MB, Frazier RC, Vicini FA, Yan D, Matter RC, Martinez AA, Wong JW. Intensity modulation to improve dose uniformity with tangential breast radiotherapy: initial clinical experience. Int J Radiat Oncol Biol Phys., 48(5):1559-68, 2000.

3.Ostwald PM, Kron T, Hamilton CS, Denham JW. Clinical use of carbon-loaded thermoluminescent dosimeters for skin dose determination. Int J Radiat Oncol Biol Phys., 33(4):943-50, 1995.