Kumar Narendra, Hanumanthappa Nikesh, Miriyala Raviteja, Vyas Sameer, Salunke Pravin, Oinam Arun S, Yadav Budhi S, Madan Renu, Dracham Chinnababu, Kapoor Rakesh
Department of Radiotherapy, PGIMER, Chandigarh, India.
Department of Radiodiagnosis, PGIMER, Chandigarh, India.
Asia Pac J Clin Oncol. 2019 Oct;15(5):e103-e108. doi: 10.1111/ajco.13111. Epub 2019 Jan 30.
Conformal radiation is the standard of care in treatment of glioblastoma. Although co-registration of magnetic resonance imaging (MRI) with early contrast enhanced computed tomography (CECT) is recommended for target delineation by consensus guidelines, ground realities in developing countries often result in availability of less-than-ideal MR sequences for treatment planning. Purpose of this study is to analyze the impact of incorporation of delayed-CECT sequences for radiation planning in glioblastomas, as an adjunct or alternative to MRI.
Case records of all patients of glioblastoma treated at our center between 2011 and 2014 were retrospectively evaluated. Gross treatment volumes were delineated on T1 contrast MRI (m-GTV), early CECT (e-GTV) and delayed CECT (d-GTV); volumetric comparisons were made using repeated measures analysis of variance and pair-wise analysis.
Although 96% of registered patients underwent postoperative MRI, only 38% of them had desirable sequences suitable for co-registration. Median duration between acquisition of postoperative MRI and surgery was 45 days (range, 33-60), whereas that between MRI and treatment-planning CT was 5 days (range, 1-10). Statistically significant differences (P < 0.0001) were obtained between mean volumes of e-GTV (41.20cc), d-GTV (58.09cc) and m-GTV (60.52cc). Although the mean GTV increased by 46% between early CECT and MRI, the difference was only 4% between delayed CECT and MRI.
Delayed CECT is superior to early CECT for co-registration with MRI for target delineation, especially when available MR sequences are less-than-ideal for treatment planning, and can be considered as the most appropriate adjunct as well as an alternative to MRI, compared to early CECT.
适形放疗是胶质母细胞瘤治疗的标准方法。虽然根据共识指南，建议将磁共振成像（MRI）与早期增强计算机断层扫描（CECT）进行联合配准以勾画靶区，但发展中国家的实际情况往往导致用于治疗计划的MR序列不理想。本研究的目的是分析将延迟CECT序列纳入胶质母细胞瘤放疗计划的影响，作为MRI的辅助手段或替代方法。
回顾性评估2011年至2014年在本中心接受治疗的所有胶质母细胞瘤患者的病例记录。在T1加权增强MRI（m-GTV）、早期CECT（e-GTV）和延迟CECT（d-GTV）上勾画大体肿瘤体积；使用重复测量方差分析和两两分析进行体积比较。
虽然96%的登记患者接受了术后MRI检查，但其中只有38%的患者有适合联合配准的理想序列。术后MRI检查与手术之间的中位间隔时间为45天（范围33 - 60天），而MRI与治疗计划CT之间的间隔时间为5天（范围1 - 10天）。e-GTV（41.20cc）、d-GTV（58.09cc）和m-GTV（60.52cc）的平均体积之间存在统计学显著差异（P < 0.0001）。虽然早期CECT与MRI之间的平均GTV增加了46%，但延迟CECT与MRI之间的差异仅为4%。
在与MRI联合配准以勾画靶区方面，延迟CECT优于早期CECT，特别是当可用的MR序列对于治疗计划不太理想时，与早期CECT相比，延迟CECT可被视为最合适的辅助手段以及MRI的替代方法。
