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Radiation Dose in Radiotherapy from Prescription Deliveryto IAEA-TECDOC-896 XA9642841 Radiation dose in radiotherapy from prescription deliveryto INTERNATIONAL ATOMIC ENERGY AGENCY The originating Sectio f thino s publicatio IAEe th Ann i was : Dosimetry Section International Atomic Energy Agency Wagramerstrasse5 0 10 x P.OBo . A-1400 Vienna, Austria RADIATION DOSE IN RADIOTHERAPY FROM PRESCRIPTION TO DELIVERY IAEA, VIENNA, 1996 IAEA-TECDOC-896 ISSN 1011-4289 IAEA© , 1996 Printed by the IAEA in Austria August 1996 The IAEA does not normally maintain stocks of reports in this series. However, microfiche copie f thesso e reportobtainee b n sca d from IN IS Clearinghouse International Atomic Energy Agency Wagramerstrasse 5 P.O. Box 100 A-1400 Vienna, Austria Orders shoul accompaniee db prepaymeny db f Austriao t n Schillings 100,- for e for e chequ a th f m th IAE mf o n o i n i r Aeo microfiche service coupons which may be ordered separately from the INIS Clearinghouse. FOREWORD Cancer incidenc increasins ei developen gi developin weln s i d a s la g countries. However, sinc somn ei e advanced countrie cure sth e rat increasins ei g faster tha cancee nth r incidence rate, the cancer mortality rate is no longer increasing in such countries. The increased cure rate ca attributee nb earlo dt y diagnosi improved san d therapy othee th rn handO . , until recently, in some parts of the world - particularly in developing countries - cancer control and therapy programmes have had relatively low priority. The reason is the great need to control communicable diseases. Toda yrapidla y increasing numbe thesf ro e disease undee sar r control. Thus ,expectee canceb y becomma ro d t eprominena t proble thid msan will resul publin i t c pressure for higher priorities on cancer care. The creation of adequate treatment facilities and the training of the necessary personnel will take time, in some cases 10 to 15 years. In some relatively advanced developing countries radiation therapy is applied in about detectel 50al f %o d cancer cases. Approximately hal thesf o f e treatments have curative intent. Surgery and radiotherapy applied individually or combined result in the cure of about 40% of all patients. The application of chemotherapy alone has curative effects only on a small percentag e canceth f eo r patients. Moreover, palliative radiotherap s oftei y n excellenn i t providing prolonged increased lifan e d life qualit patientr yfo s with incurable cancer. encouragins i t I noto gt e tha resulte tth s achieve radiatioy db n therapy show continuous improvement. This can be traced back to a number of developments: increased knowledge regarding rumour and normal tissue response to radiation, early diagnosis with improved tumour localisation, improved dosimetr dosd yan e planning e introductioTh . f moderno n equipment (CT-scanners, ^Co-units, linear accelerators, computerised treatment planning systems, etc.) has been crucial in these developments and makes possible a more accurate target delineation, better treatment planning resulting in irradiation of the Planning Target Volume (PTV) with a highly uniform dose and, simultaneously, a reduction in dose to healthy tissues outside the PTV. Experience shows that high quality radiotherap onln achieveye ca y b conductes i t i f di d by a skilled team working closely together with good communication between various categories of staff. The team must consist of radiation oncologists, radiation physicists and radiographers alss i t oI . shown that dose prescribe dosd dan e delivered hav agreo et e within +/- 5 % in the PTV to achieve a controlled cure rate without excessive complications to normal tissue. Due to the increasing demands for high accuracy in dose delivery, one of the goals of the seminadeao t s differene l witth wa r l hal t step treatmenn si t procedure fro decisioe mth n of treatment strategy to the quality assurance of the treatments. In some advanced developing countrie sespeciall- Latin yi n Americs i tren e w th ad- no to move from ^Co-unit lineao st r accelerators. Absolute dose wels sa s dos a l e distributions fro lattee mth r typ therapf eo y machine easiln s ca alterevar e yd b yan d through service actions or faulty parts. Therefore, seminar trainind san g courses coverin aspectl gal qualitf so y control in radiotherap d dosimetran y f greao e ty ar importanc should ean e helb d d regionallr yo nationall regulaa n yo r basis. EDITORIAL NOTE preparingIn this publication press,for IAEAthe staffof have pages madethe up from the original manuscripts submittedas authors.the viewsby The expressed necessarilynot do reflect those governmentsofthe nominating ofthe Member nominating the States of or organizations. Throughout textthe names Memberof States retainedare theyas were when textthe was compiled. The use of particular designations of countries or territories does not imply any judgement by publisher,the legalthe IAEA,to statusthe as of such countries territories,or of their authoritiesand institutions delimitation ofthe or theirof boundaries. mentionThe of names of specific companies productsor {whether indicatednot or registered)as does implyintentionnot any infringeto proprietary rights, should construednor be it an as endorsement or recommendation on the part of the IAEA. The authors are responsible for having obtained the necessary permission for the IAEA to reproduce, translate materialuse or from sources already protected copyrights.by CONTENTS L ACCURACY REQUIREMENTS IN RADIOTHERAPY Tumo normad an r l tissue response fractionateo st d non-uniform dose delivery ......9 . P. Kallman, A. Âgren, A. Brahme Converting dose distributions into tumour control probability ................... 27 A.E. N ahum Definition of treatment geometry in radiation therapy ........................ 41 P. Acdtonen Dosimetric precision requirements and quantities for characterizing the response of tumors and normal tissues ........................................ 49 BrahmeA. DL EQUIPMENT REQUIREMENTS Lessons learned from accident radiotherapn si y ............................9 6 . Ortiz-Lopez,P. Novotny,J. HaywoodJ. Review of WHO/PAHO/IAEA recommendations concerning radiotherapy facilities . 83 O.P. Hanson Alternative design megavoltagr sfo e machine r cancesfo r treatmen developinn i t g countries ....................................................3 9 . C. Bonus, Svensson,H. G.P. Hanson Simulation and radiation treatment in external radiotherapy .................. 101 E. Singer Analysis of variations in the dose delivered in radiation therapy ............... 107 D.B. Feld m(a). INTERCOMPARISON role f SSDL-Helsinkeo Th r dosimetrfo i qualitd yan y audi radiotherapn i t y .......3 11 . P. Aaltonen SSDL Argentina: Dosimetric intercomparison programm r cobalefo 0 6 t therapy units ................................................. 123 Saravi,M. Papadopulos,S. MugliaroliH. A program on quality assurance and dose calibration for radiation therapy units in Venezuela ................................................... 135 M.C. de Padilla, L. Carrizales, J. Diaz, F. Gutt, A. Cozman IIKb). DOSIMETRY PROCEDURES Radiation dosimetry with plane-parallel ionization chambers: An International (IAEA) Code of Practice [Invited Paper] ................. 143 P. Andreo, P.R. Almond, O. Mattsson, A.E. N ahum, M. Roos An algorith mincludo t bremsstrahlune eth g componen determinatioe th n i t e th f no absorbed dose in electron beams ................................... 159 S.C. Klevenhagen Clinical dosimetry with plastic scintillator salmos- t energy independent, direct absorbed dose reading with high resolution ............................ 165 U. Quast, Flühs,D. KolanoskiH. Absorbed dose beam quality factors for cylindrical ion chambers: Experimental photoV determinatioM 5 n1 beamd an s6 t na ......................... 1 17 . C. Caporali, A .S. Guerra, R.F. Laitano, M. Pimpinella Displacement correction factor versus effective poin f measuremeno t deptn i t h dose curve measurements at 60Co gamma rays .......................... 179 Bruno,A. G.R. Vêlez, BrunetteM. An analysi f somso e aspect attenuation-scattee th f so r function brachytherapn i s y dosimetry ................................................... 185 S.C. Klevenhagen Standardization of indium-192 coiled source in terms of air kerma output. ........ 199 Shanta,A. Unnikrishnan,K. U.B. Tripathi, Kannan,A. P.S. lyer Calibratio 192f no Ir high dose rate brachytherapy sources ....................3 20 . M.H. Maréchal, C.E. de Almeida, C.H. Sibata Quality control of Ir-192, Cs-137 and Ra-226 sources for use in brachytherapy ..... 207 C.H. Oyarzûn Cortes, PalmaD.,AM. PenalozaH. TomicicM. C., . QUALITIV Y ASSURANCE NETWOR RADIOTHERAPKN I Y Quality Assurance Network: the European pilot study ....................... 213 J. Chavaudra, Dutreix,A. Deireumaux,S Schuerender Brider,A. van E. V. QUALITY ASSURANCE PROGRAMM RADIOTHERAPEN I Y Minimum requirement prograA Q a radiatiomn n i so n oncology ...............7 23 . P.R. Almond Accurac radiosurgeryn yi influence Th : f collimatoeo r diameterc ar d san weight dose th en distributioso r singlnfo e target .......................1 25 . M.C. Plazas, D. Leflcopoulos, M. Schlienger, L. Merienne Dosimetry of breast cancer .......................................... 259 G. Ramirez C., J. Restrepo, CA. Aguirre Platon V2.0 & BRA VI.0 system for teletherapy and brachytherapy ............. 263 C. Aries, Coscia,G. LuongoA. Thermoluminescence dosimetry applie qualito dt y assuranc radiotherapyn ei , brachytherapy and radiodiagnostic .................................. 267 G. Marinello SUMMAR
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