Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Radiation Oncology cung cấp cho các bạn kiến thức về ngành y đề tài: Comparison of simple and complex liver intensity modulated radiotherapy. | Lee et al. Radiation Oncology 2010 5 115 http content 5 1 115 RADIATION ONCOLOGY RESEARCH Open Access Comparison of simple and complex liver intensity modulated radiotherapy MarkT Lee1 2 3 Thomas G Purdie1 Cynthia L Eccles3 Michael B Sharpe1 Laura A Dawson13 Abstract Background Intensity-modulated radiotherapy IMRT may allow improvement in plan quality for treatment of liver cancer however increasing radiation modulation complexity can lead to increased uncertainties and requirements for quality assurance. This study assesses whether target coverage and normal tissue avoidance can be maintained in liver cancer intensity-modulated radiotherapy IMRT plans by systematically reducing the complexity of the delivered fluence. Methods An optimal baseline six fraction individualized IMRT plan for 27 patients with 45 liver cancers was developed which provided a median minimum dose to cc of the planning target volume PTV of Gy range Gy in 6 fractions while maintaining liver toxicity risk 5 and maximum luminal gastrointestinal structure doses of 30 Gy. The number of segments was systematically reduced until normal tissue constraints were exceeded while maintaining equivalent dose coverage to 95 of PTV PTVD95 . Radiotherapy doses were compared between the plans. Results Reduction in the number of segments was achieved for all 27 plans from a median of 48 segments range 34-52 to 19 segments range 6-30 without exceeding normal tissue dose objectives and maintaining equivalent PTVD95 and similar PTV Equivalent Uniform Dose EUD -20 IMRT plans with fewer segments had significantly less monitor units mean 1892 reduced to 1695 p but also reduced dose conformity mean RTOG Conformity Index increased to p . Conclusions Tumour coverage and normal tissue objectives were maintained with simplified liver IMRT at the expense of reduced conformity. Background Conformal liver radiotherapy CRT has an emerging role in treating .
