الفهرس 
TitleOnly 14 pages are availabe for public view
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Abstract
Bladder cancer is the most common cancer and second most common cause of cancer related morality in men. Radiotherapy and surgery are considered as definitive treatment for bladder cancer beside to adjuvant
Chemotherapy or hormonal therapy. Three -dimension conformal radiotherapy and intensity modulated radiotherapy technique focus of radiation fields according to tumor size description, position of tumor and tumor depth inside the body, these plans of radiation aim to treat target tumor with high radiation dose and reduce radiation dose to organ at risk to minimum. Each plan depends on factor to deliver dose includes two- dimension planning or three -dimension planning system, type of radiation energy, number of fields and its directions used, these factors effects quality of treatment and reduce side effects to surroundingorganssuch rectum, small bowel and both head of femur.
This study used linear accelerator one energy (Elekta©), multi slice computed tomography and three- dimension planning system and simulator.
The aim is to study Dosimetric Comparison of intensity modulated therapy and 3D conformal Radiotherapy Plans and treatment of bladder tumors using intensity Modulated therapy.
These study where done as following:
• Simulation is done for 50 bladder cancer patients in spine position, patient underwent computed tomography with 3 mm thickness in each slice, patient is asked to full their bladder and to empty their rectum, CT images is sent to treatment planning system.
• Target definition is done at images of CT for bladder and seminal vesicles and countering for rectum, small bowel and femoral heads is done also.
• 3D conformal radiation is used to deliver dose of 64Gy to bladder as target and to spare organ at risk using multileaf collimator in two phases.
• In three- dimension conformal radiotherapy technique is used in boost after using of box technique for phase one, for thesefields in each plan we used with high energy 10Mev InIntensity modulated therapy is used to deliver 64Gy to bladder as target and to spare organ at risk, Thetechnique with modulated (IMRT)for 9 fields for 2 phases with low energy 6Mev
• Dose volume histogram analysis is done to all planes to compare which plan is better to achieve radiotherapy goals of minimizing dose to critical organs.
These study shows that in IMRT radiotherapy, better distribution to dose and more spare to organ where there was the use of low energy in the IMRT plans (6Mev) is the better than using the high energy in the 3D plans it also shows intensity modulated radiotherapy on beams energy, where 6MV plans gives better dose to target and more spare to organ at risk and also IMRTplans gives better dose distribution to Bladder and decreased dose to organ at risk than 3D conformal radiotherapy
The study recommended the use of intensity modulated therapy plans. As technique improve tumor control probability. Reduce radiation induced toxicity and improved critical tissue spring.
Summary, Conclusion & Recommendations
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5.2. Conclusions The work done in this study stresses the advantages and disadvantages of two treatment methods for bladder tumors. To choose between two techniques it is necessary to see the fifty patient’s characteristics case by case. It is important the total dose which has to be given to the planning target volume. When the doctor decides to give to treatment planning volume a total dose which creates the possibility to have dose for the organs at risk under the dose limits it will be preferable to use IMRT technique because it is less time consuming for QC and more comfortable for the patient which in this case has to stay less time in the machine during the treatment. For the cases when the doses which have to be given to the treatment planning volume will be large, around, 64 Gy it will be use IMRT technique as the best solution for keeping the doses to organ at risk in the permitted level.