Experience of the Commissioning and Implementation the Total Skin Electron Therapy (TSET) at Siriraj Hospital
Abstract
Objective: TSET at our institution has been commissioned. Technique and dosimetry were investigated and reported.
Methods & Materials: According to the Stanford six-dual field technique, using a high dose rate (888 MU/min) mode 6 MeV electron, at 400 cm SSD, on Varian 23 EX linear accelerator, investigation for the optimal irradiation geometry and TSET dosimetric features were performed.
Results: Acceptable field symmetry was obtained at the gantry angle ± 17.5° from 90°. Using a 1 cm perspex scatterer, the electron mean energy was degraded from 6 MeV to 2.1 MeV. Depth of dose maximum was detected at the surface to a depth of 2 mm. with R80 and R50 were at 0.52 and 0.9 cm from the surface. respectively. Absolute dose to water at a calibration point from the dual gantry in the high dose rate mode delivery was 1.367 Gy/1000 MU. The overlap factor (B) in this study was found to be 2.93. Phantom dosimetry revealed the accuracy of delivered dose was within ± 5%. Skin dose distribution was within ± 10%. of the dose at prescription point and the x-ray background dose averaged over a phantom body was 0.58%. Dose homogeneity over the patient’s flat surface varied only a few percents. But at the tangential surfaces, the 10-30% difference from the delivered dose were presented.
Conclusion: TSET procedure for our first mycosis fungoides patient was successfully commissioned and implemented to the patient. Acceptable dosimetric features with the high dose rate electron mode were achieved. At one year follow-up, a satisfactorily clinical result was detected from the given technique.
Downloads
Metrics
References
Nisce LZ, Chu CHF, Lee SH . et al. Total skin electron beam therapy for cutaneous lymphomas and leukemias. Int J Radio Oncol! Biol Phys 1982:8:1587-92.
RaviA,. Nisce LZ, Nori D. Total skin electron beam therapy in the management of cutaneous malignancies. Clinics in Dermatology 2001;19:354-6.
Tetenes PJ. Goodwin PN. Comparative study of superficial whole-body radiotherapeutic techniques using a 4 MeV nonangulated beam. Radiology 1977;122:219-26.
Williams PC, Hunter RD, Jackson SM. Whole body electron therapy in mycosis fungoides - a successful translation technique achieved by modification of an established linear accelerator. Br J Radiol 1979:52:302-7
Podgorsak EB, Podgorsak MB. Special Technique in radiotherapys Part B Total skin electron irradiation. In Van Dyk J: The modern technology of radiation oncology. Medical physics publishing , Madison WI, USA, 1999: 663-78.
American Association of Physicist in Medicine. Total Skin Electron Therapy. Technique and Dosimetry. AAPM Report No. 23. American Institutes of Physics Inc & New York, USA. 1988
Das lJ, Copeland GF, Bushe HS. Spatial distribution of bremstrahlung in a dual electron beam used in total skin treatment: Errors due to ionization chamber cable irradiation. Med Phys 1994:21(110):1733-8
Chen Z. Agostinelli A, Nath R. On the use of unshield cables in ionization chamber dosimetry for total skin electron therapy. Phys Med Biol 1998:43:539-46.
International Atomic Energy Agency. Absorbed dose determination in external beam radiotherapy. Technical reports series No. 398 IAEA & Vienna, Austria, 2000
Jones GW, Trados A, Hodson DI, Rosenthal D, Roberts J. Thorson B. Prognosis with newly diagnosed mycosis fungoides after total skin electron radiation of 30 Gy or 35 Gy. Int J Radiat Oncol Biol Phys 1994:28:839.
American Association of Physicist in Medicine. Total Skin Electron Therapy. Technique and Dosimetry. AAPM Report No. 23. American Institutes of Physics Inc & New York, USA 1988:39.
Antolak JA, Cundiff JF, Ha CS. Utilization of thermoluminescent dosimetry in total skin electron beam radiotherapy of mycosis fungoides. Int J Radiat Oncol Biol Phys 1998; 40(1):101-8.
American Association of Physicist in Medicine. Total Skin Electron Therapy, Technique and Dosimetry. AAPM Report No. 23. American Institutes of Physics Inc & New York, USA 1988:39.
Anacak Y, Arigan C, Bar-Deroma R, Tamir A, Kuten A. Total skin electron irradiation: Evaluation of dose uniformity throughout the skin surface. Medical Dosimetry 2003; 28(1):31-4.
El-Khatib E, Hussein S. Nikolic M, Voss NJ. Parsons C. Variation of electron beam uniformity with beam angulation and scatter position for total skin irradiation with the Stanford technique. Int J Radiat Oncol Biol Phys 1995: 33:469-74.
Weaver RD, Gerbi BJ, Dusenberg KE. Evaluation of dose variation during total skin electron irradiation using thermoluminescent dosimeters. Int J Radiat Oncol Biol Phys 1995:33:475-8.
Desai KR. Pezner RD, Lipsett JA, et al. Total skin electron irradiation for mycosis fungoides: Relationship between acute toxicities and measured dose at different anatomic sites. Int J Radiat Oncol Biol Phys 1988:15:641-5.
Chen Z, Agostinelli AG, Wilson L, Nath R. Matching the dosimetry characteristics of a dual-field Stanford technique to a customized single-field Stanford technique for total skin electron therapy. Int J Radiat Oncol Biol Phys 2004:59(3):872-85.
Peters VG, Jaywant SM. Implementation of total skin electron therapy using an optional high dose rate mode on a conventional linear accelerator. Medical Dosimetry 1995:20(2):99-104.
Parida DK, Verma KK, Chander S. Joshi RC, Rath GK. Total skin electron irradiation therapy in mycosis fungoides using high-dose rate mode: Preliminary experience. International Journal of Dermatology 2005:44:828-30.
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2023 The ASEAN Journal of Radiology
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Disclosure Forms and Copyright Agreements
All authors listed on the manuscript must complete both the electronic copyright agreement. (in the case of acceptance)
