Rosa C, Caravatta L, Delli Pizzi A, Di Tommaso M, Cianci R, Gasparini L, Perrotti F, Solmita J, Sartori S, Zecca I A L, Di Nicola M, Basilico R, Genovesi D
Department of Radiation Oncology, SS. Annunziata Hospital, "G. D'Annunzio" University, Via Dei Vestini, 66100 Chieti, Italy.
Department of Radiation Oncology, SS. Annunziata Hospital, "G. D'Annunzio" University, Via Dei Vestini, 66100 Chieti, Italy.
Cancer Radiother. 2019 Jun;23(3):216-221. doi: 10.1016/j.canrad.2018.10.004. Epub 2019 May 17.
To retrospectively evaluate the inter-observer agreement between a radiologist and a radiation oncologist and volume differences, in T2 and diffusion-weighted (DWI) MRI of gross tumor volume (GTV) delineation, in rectal cancer patients.
Two observers, a radiologist and a radiation oncologist, delineated GTVs of 50 patients on T2-weighted MRI (T2) and echo planar DWI (DWI). Observers agreement was assessed using DICE index, Bland-Altman analysis and intra-class correlation coefficient (ICC). Student's t-test was used for GTV comparison.
Median T2 and DWI were 17.09±14.12 cm (1.92-62.03) and 12.79±12.31 cm (1.23-62.25) for radiologist, and 16.82±13.66 cm (1.78-65.9) and 13.72±12.77 cm (1.29-69.75) for radiation oncologist. T2 were significantly larger compared to DWI (P<0.001 and P<0.001, for both observers). Mean DICE index for T2 and DWI were 0.80±0.07 and 0.77±0.06. The mean difference between the two observers were 0.26cm (95% CI: -5.36 to 5.88) and -1.13cm (95% CI: -5.70 to 3.44) for T2 and DWI volumes. The ICC for T2 volumes was 0.989 (95% CI: 0.981-0.994) (P<0.001) and 0.992 (95% CI: 0.986-0.996) (P<0.001) for DWI volumes.
DWI resulted in smaller volumes delineation compared to T2-weighted MRI. Substantial and almost perfect agreements were reported for DWI and T2 between radiologist and radiation oncologist. Due to the fact that DWI could be considered a simple technique for volume delineation for radiation oncologist, DWI could be used to improve quality in radiation planning for an accurate boost volume delineation when a dose escalation is investigated.
回顾性评估放射科医生与放射肿瘤学家之间在直肠癌患者大体肿瘤体积（GTV）的T2加权和扩散加权（DWI）磁共振成像（MRI）中观察者间的一致性以及体积差异。
两名观察者，一名放射科医生和一名放射肿瘤学家，在T2加权MRI（T2）和回波平面DWI（DWI）上勾勒出50例患者的GTV。使用DICE指数、Bland-Altman分析和组内相关系数（ICC）评估观察者间的一致性。采用学生t检验进行GTV比较。
放射科医生的T2和DWI中位数分别为17.09±14.12 cm（1.92 - 62.03）和12.79±12.31 cm（1.23 - 62.25），放射肿瘤学家分别为16.82±13.66 cm（1.78 - 65.9）和13.72±12.77 cm（1.29 - 69.75）。与DWI相比，T2明显更大（两名观察者的P均<０.００１）。T2和DWI的平均DICE指数分别为0.80±0.07和0.77±0.06。两名观察者在T2和DWI体积上的平均差异分别为0.26cm（95%CI：-5.36至5.88）和-1.13cm（95%CI：-5.70至3.44）。T2体积的ICC为0.989（95%CI：0.981 - 0.994）（P<0.001）,DWI体积的ICC为0.992（95%CI：0.986 - 0.996）（P<0.001）。
与T2加权MRI相比，DWI勾勒出的体积更小。放射科医生与放射肿瘤学家在DWI和T2方面报告了实质性且几乎完美的一致性。由于DWI可被视为放射肿瘤学家进行体积勾勒的一种简单技术，在研究剂量递增时，DWI可用于提高放射治疗计划的质量，以准确勾勒出加量体积。
