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Background: Fractionated external beam radiotherapy followed by intracavitary brachytherapy is the mainstay of treatment in cervical cancer. Due to long radiotherapy course, patients in developing countries default effective radiotherapy. Treatment break or discontinuance leads to treatment failure. Continuous hyperfractionated accelerated radiotherapy (CHART) is an altered fractionation scheme used to reduce overall treatment time, overcome tumor repopulation thus could be an option in cervical carcinoma.Methods: Twenty-five histopathological documented locally advanced cervical carcinoma (FIGO stage IB2-IVA) were treated with 42Gy/30fractions external radiotherapy over 10-day period at an inter-fraction interval of 6 hours using CHART technique. Following CHART, patients were subjected to high dose rate brachytherapy to a dose schedule of 9Gyx2 at weekly interval. The response to above radiotherapy protocol and morbidity pattern was evaluated.Results: All patients completed planned CHART external radiotherapy. The median follow-up was 32-months with a pelvic control rate of 68% and 24-month overall survival was 72%. The most common acute toxicity in CHART technique was fatigue (64%) and diarrhea (52%), the late effects being rectal bleeding (2-cases), subcutaneous fibrosis (1-case), spinal pain (1-case). Conclusion:CHART technique is an effective and well tolerated technique in locally advanced cervical cancer at a cost of manageable fatigue and diarrhea. Further investigation involving large number of patients is warranted to evaluate this technique.

The fi rst part of this study was about measurement of dosimetric parameters for small photon beams to be used as input data for treatment planning computer system (TPS) No. 50 (1994) that dose delivered to the target volume must be within ± 5% error. No. 50 (1994), bahawa dos yang diberikan kepada isipadu sasaran mesti berada dalam ketakpastian ± 5%. Keywords: Stereotactic radiosurgery (SRS); treatment planning system (TPS); pinpoint ionisation chamber; thermoluminiscent detector (TLD); dose verifi cation ABSTRAK Bahagian pertama kajian ini adalah mengenai pengukuran parameter dosimetri bagi bim foton halus untuk digunakan sebagai data input bagi sistem perancangan rawatan berkomputer (TPS) dan untuk mengesahkan dos yang dikira oleh TPS dalam prosedur radiosurgeri stereotaktik (SRS). Data bim yang diperlukan adalah peratus dos kedalaman (PDD), nisbah paksi terluar (OAR) dan faktor penyerakan. Bim halus berdiameter 5 mm hingga 45 mm daripada kolimator kon membulat dalam SRS digunakan bagi pengukuran data bim. Pengukuran dilakukan menggunakan kebuk pengionan bersaiz kecil (0.016cc). Dalam bahagian kedua kajian ini, kami laporkan kepentingan melaksanakan prosedur jaminan kualiti

Radiological characterization and water equivalency of genipin gel for x-ray and electron beam dosimetry Tina Gorjiara, Robin Hill, Zdenka Kuncic et al. Abstract. For a polymer gel dosimeter to be of use in radiation dosimetry, it should display water-equivalent radiological properties. In this study, the radiological properties of the MAGIC (Methacrylic and Ascorbic acid in Gelatin Initiated by Copper) normoxic polymer gels were investigated. The mass density ( ) was determined based on Archimedes principle. The weight fraction of elemental composition and the effective atomic number (Z eff ) were calculated. The electron density was also measured with 90° scattering angle at room temperature. The linear attenuation coefficient (µ) of unirradiated gel, irradiated gel, and water were determined using Am-241 based on narrow beam geometry. Monte Carlo simulation was used to calculate the depth doses response of MAGIC gel and water for 6MV photon beam. The weight fractions of elements composition of MAGIC gel were close to that for water. The mass density was found to be 1027 ± 2 kg m 3 , which is also very close to mass density of muscle tissue (1030 kg m 3 ) and 2.7% higher than that of water. The electron density ( e ) and atomic number (Z eff ) were found to be 3.43 × 10 29 e m 3 and 7.105, respectively. The electron density measured was 2.6% greater than that for water. The atomic number was very close to that for water. The prepared MAGIC gel was found to be water equivalent based on the study of element composition, mass density, electron density and atomic number. The linear attenuation coefficient of unirradiated gel was very close to that of water. The µ of irradiated gel was found to be linear with dose 2-40 Gy. The depth dose response for MAGIC gel from a 6 MV photon beam had a percentage dose difference to water of less than 1%. Therefore it satisfies the criteria to be a good polymer gel dosimeter for radiotherapy.

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