INTRODUCTION For accurate dose calculations, it is necessary to provide a correct relationship between the CT numbers and electron density in radiotherapy treatment planning systems (TPSs). The purpose of this study was to investigate the energy dependence of measured CT numbers on substituted materials used for CT number calibration of radiotherapy TPSs and the resulting errors in the treatmen...

introduction proton therapy is used to treat malignant tumors such as melanoma inside the eye. proton particles are adjusted according to various parameters such as tumor size and position and patient’s distance from the proton source. the purpose of this study was to assess absorbed doses in eyes and various tumors found in the area of sclera and choroid and the adjacent tissues in radiotherap...

Osteosarcoma (OS) is a malignant tumor of the bone derived from primitive transformed cells of the mesenchymal origin. Local low-linear energy transfer (LET) radiotherapy has limited benefits on OS owing to its radioresistance. Thus, this study aimed to investigate the effects of high-LET radiation on human OS. Therefore, the human OS cell lines, U2O2 and KHOS/NP, were examined in vitro, or an ...

Laser palliation for advanced rectal or rectosigmoid cancer requires repeat treatments every four to six weeks. Thirteen patients (seven men, six women) age range 65-91 (median 81) received additional external beam radiotherapy in an attempt to reduce the frequency of laser treatments required. After successful laser recanalisation, patients were treated with a dose of 30-55 Gy in 10-20 fractio...

(3) The advances in radiotherapy have been somewhat less spectacular, although most radiotherapy centres now possess modern apparatus of formidable energy. Nevertheless in spite of renewed surgical and radiotherapeutical efforts, there is no real evidence to show that the prognosis for sufferers from laryngopharyngeal cancer has materially improved in the last decade. As far as radiotherapy is ...

Introduction Intensity-Modulated Radiotherapy (IMRT) is becoming an increasingly routine treatment method. IMRT can be delivered by use of conventional Multileaf Collimators (MLCs) and/or physical compensators. One of the most important factors in selecting an appropriate IMRT technique is integral dose. Integral dose is equal to the mean energy deposited in the total irradiated volume of the p...