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: Inter-observer variability in contouring the penile bulb on CT images for prostate cancer treatment planning. | Perna et al. Radiation Oncology 2011 6 123 http content 6 1 123 RADIATION ONCOLOGY RESEARCH Open Access Inter-observer variability in contouring the penile bulb on CT images for prostate cancer treatment planning I I K i .i l r-c r -7-7-irini2 l-locir-icirsì illi 1 l-dlir- 3 Psir-icsiti4 l ld cmi4 Lucid renid Cesare Cozzanni Eleonora Iviaggiulli Gianni Fellin Tiziana Rdiican Riccardo Vdlddgni Vittorio Vavassori5 Sergio Villa6 and Claudio Fiorino1 Abstract Several investigations have recently suggested the existence of d correlation between the dose received by the penile bulb PB and the risk of erectile dysfunction ED after radical radiotherapy for clinically localized prostate carcinoma. A prospective multi-Institute study DUE-01 was implemented with the aim to assess the predictive parameters of ED. Previously an evaluation of inter-observer variations of PB contouring was mandatory in order to quantify its impact on PB dose-volume parameters by means of a dummy run exercise. Fifteen observers from different Institutes drew the PB on the planning CT images often patients inter-observer variations were analysed in terms of PB volume variation and cranial caudal limits. 3DCRT treatment plans were simulated to evaluate the impact of PB contouring inter-variability on dose-volume statistics parameters. For DVH analysis the values of PB mean dose and the volume of PB receiving more than 50 Gy and 70 Gy V50 and V70 respectively were considered. Systematic differences from the average values were assessed by the Wilcoxon test. Seven observers systematically overestimated or underestimated the PB volume with deviations from the average volumes ranging between -48 and 34 p . The analysis of the cranial and caudal borders showed a prevalence of random over systematic deviations. Inter-observer contouring variability strongly impacts on DVH parameters although standard deviations of interpatient differences were larger than inter-observer .
