■任务组43(TG-43)形式主义不考虑组织和涂药器的异质性。这项研究是比较基于模型的剂量计算算法的效果,像先进的折叠锥引擎(ACE),关于宫颈癌患者的剂量计算与TG-43剂量计算形式主义。
■前瞻性研究了20例接受高剂量率腔内近距离放射治疗的宫颈癌患者。在Oncentra治疗计划系统(Elekta,Veenendaal,荷兰)。所有患者均计划使用钴60(Co-60)和铱192(Ir-192)来源,剂量为21Gy,分3次。这些计划是用TG-43形式主义和基于模型的剂量计算算法ACE计算的。在目标覆盖率和OAR剂量方面比较了TG-43和基于ACE的计划的剂量学参数。
■对于基于Co-60的计划,高风险临床目标体积(HR-CTV)的D90和V100值的百分比差异分别为0.36±0.43%和0.17±0.31%,分别。对于膀胱,直肠和乙状结肠,D2cc体积的百分比差异为-0.50±0.51%,-0.16±0.53%和-0.37±1.21%,分别。对于基于Ir-192的计划,HR-CTV的D90百分比差异为0.54±0.79%,而V100为0.24±0.29%。对于膀胱,直肠和乙状结肠,2cc体积的剂量为0.35±1.06%,0.99±0.74%和0.74±1.92%,分别。用ACE和TG-43计算的剂量学参数没有发现显着差异。
■ACE算法减少了OAR和目标的剂量。然而,ACE和TG-43在两种来源的靶标和OAR的剂量学参数中没有显示出显着差异。
UNASSIGNED: Task Group 43 (TG-43) formalism does not consider the tissue and applicator heterogeneities. This study is to compare the effect of model-based dose calculation algorithms, like Advanced Collapsed Cone Engine (ACE), on dose calculation with the TG-43 dose calculation formalism in patients with cervical carcinoma.
UNASSIGNED: 20 patients of cervical carcinoma treated with a high dose rate of intracavitary brachytherapy were prospectively studied. The target volume and organs at risk (OARs) were contoured in the Oncentra treatment planning system (Elekta, Veenendaal, The Netherlands). All patients were planned with cobalt-60 (Co-60) and iridium-192 (Ir-192) sources with doses of 21 Gy in 3 fractions. These plans were calculated with TG-43 formalism and a model-based dose calculation algorithm ACE. The dosimetric parameters of TG-43 and ACE-based plans were compared in terms of target coverage and OAR doses.
UNASSIGNED: For Co-60-based plans, the percentage differences in the D90 and V100 values for high-risk clinical target volume (HR-CTV) were 0.36 ± 0.43% and 0.17 ± 0.31%, respectively. For the bladder, rectum and sigmoid, the percentage differences for D2cc volumes were -0.50 ± 0.51%, -0.16 ± 0.53% and -0.37 ± 1.21%, respectively. For Ir-192-based plans, the percentage difference in the D90 for HR-CTV was 0.54 ± 0.79%, while V100 was 0.24 ± 0.29%. For the bladder, rectum and sigmoid, the doses to 2cc volume were 0.35 ± 1.06%, 0.99 ± 0.74% and 0.74 ± 1.92%, respectively. No significant differences were found in the dosimetric parameters calculated with ACE and TG-43.
UNASSIGNED: The ACE algorithm reduced doses to OARs and targets. However, ACE and TG-43 did not show significant differences in the dosimetric parameters of the target and OARs with both sources.