Tong Tong, Yao Zhenwei, Xu Linhui, Cai Sanjun, Bi Rui, Xin Chao, Gu Yajia, Peng Weijun
Department of Radiology, Fudan University Shanghai Cancer Center, Shanghai, China.
J Magn Reson Imaging. 2014 Sep;40(3):738-44. doi: 10.1002/jmri.24398. Epub 2013 Oct 31.
To assess the value of maximal extramural depth (EMD) of T3 tumor spread on MRI as a potential noninvasive imaging biomarker of tumor aggressiveness in rectal cancer, by analyzing the relationship between tumoral EMD values and clinical or histological prognostic parameters. In addition, we try to investigate the relationship between EMD and apparent diffusion coefficient (ADC) values.
Ninety rectal cancer patients who underwent primary MRI staging and diffusion weighted imaging (DWI) as T3 tumor were included. Tumor EMD was measured, and the EMD values of the subgroups based on pretreatment CEA, CA19-9 levels, N stage, and histological parameters were compared. The correlation between EMD and ADC values was compared.
Interobserver agreement of confidence levels for observers 1 and 2 was good for cN stage (k = 0.678) and EMD measurement(k = 0.612) and was excellent for ADC measurement (k = 0.880). Tumor EMDs differ between CEA <5 ng/mL versus ≥ 5 ng/mL (P = 0.013), CA19-9 < 27 U/mL versus ≥ 27 U/mL (P = 0.012), the groups of cN0 versus cN+ cancers (P = 0.049), and between the several groups of histological differentiation grades (P = 0.033). There was no significant difference in EMDs between the various groups of vessel carcinoma embolus and neural invasion. A significant negative correlation (r = -0.581; P = 0.001) between ADC and EMD values was found.
Significant correlations were found between EMD values and CEA, CA19-9 level, differentiation grade and ADC value. As been found, higher EMD values were associated with a more aggressive tumor profile and, therefore, EMD has the potential to become an imaging biomarker of tumor aggressiveness indicator.
通过分析肿瘤壁外最大深度（EMD）值与临床或组织学预后参数之间的关系，评估T3期肿瘤在MRI上的壁外最大深度作为直肠癌肿瘤侵袭性潜在无创成像生物标志物的价值。此外，我们试图研究EMD与表观扩散系数（ADC）值之间的关系。
纳入90例接受T3期肿瘤初次MRI分期和扩散加权成像（DWI）的直肠癌患者。测量肿瘤EMD，并比较基于治疗前癌胚抗原（CEA）、糖类抗原19-9（CA19-9）水平、N分期和组织学参数的亚组的EMD值。比较EMD与ADC值之间的相关性。
观察者1和观察者2对cN分期（k = 0.678）和EMD测量（k = 0.612）的置信水平的观察者间一致性良好，对ADC测量（k = 0.880）的观察者间一致性极佳。CEA <5 ng/mL与≥5 ng/mL之间（P = 0.013）、CA19-9 <27 U/mL与≥27 U/mL之间（P = 0.012）、cN0与cN+癌症组之间（P = 0.049）以及几组组织学分化等级之间（P = 0.033）的肿瘤EMD存在差异。不同组的血管癌栓和神经侵犯之间的EMD无显著差异。发现ADC与EMD值之间存在显著负相关（r = -0.581；P = 0.001）。
发现EMD值与CEA、CA19-9水平、分化程度和ADC值之间存在显著相关性。如前所述，较高的EMD值与更具侵袭性的肿瘤特征相关，因此，EMD有可能成为肿瘤侵袭性指标的成像生物标志物。
