الفهرس 
TitleOnly 14 pages are availabe for public view
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Abstract
Prostate cancer is the most common cancer and second most common cause of cancer related mortality in men. Radiotherapy and surgery are considered as definitive treatment for prostate cancer beside to adjuvant chemotherapy or hormonal therapy. Three-dimension conformal radiotherapy and volumetric modulated arc therapy 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 surrounding organs such bladder, rectum, penile bulb 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 the Dosimetric Comparison of VMAT and 3D-CRT Plans and treatment of prostate tumors using volumetric Modulated arc therapy.
These study where done as following:
• Simulation is done for 50 prostate cancer patient 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 prostate and seminal vesicles and countering for bladder, rectum, penile bulb and femoral heads is done also.
• Three-dimension conformal radiotherapy is used to deliver dose of 78Gy to prostate as target and to spare organ at risk using multi leaf collimator in three phases.
• In three-dimension conformal radiotherapy 7 field technique is used in boost after using of box technique for phase one, for these 7 fields in each plan we used.
• Volumetric modulated arc therapy is used to deliver 78Gy to prostate as target and to spare organ at risk using 1 arc technique with modulated arc for each beam for 3 phases.
• 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 VMAT, better distribution to dose and more spare to organ where there was the use of VMAT better than using the 3D plans it also shows BEST spare to organ at risk and also VMAT plans gives better dose distribution to Prostate and decreased dose to organ at risk than 3D conformal radiotherapy.
• The study recommended the use of volumetric modulated arc 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 results of the current study show that the advanced technique VMAT is better in covering the tumor and more sparing of critical organs than 3D in prostate cancer treatment.
5.3. Recommendations:
Finally, we recommend the following:
Treatment of prostate cancer, Volumetric Modulated Arc Therapy is recommended than Three-dimensional Conformal Radiotherapy, due to:
• Improved critical tissue sparing.
• Improved tumor control probability.
• Decrease induced toxicity that caused by radiation.
• Leading to better quality of life and lower side effec