体素内不相干运动参数与直肠癌组织类型和病理分级的相关性研究

目的探讨体素内不相干运动（IVIM）参数与直肠癌组织学类型、病理分级的相关性。方法收集经病理证实的直肠普通腺癌29例（普通组）和黏液性腺癌12例（黏液组），术前行常规MR及10个b值（0、10、20、50、100、200、400、800、1 200、2 000 s/mm2）IVIM序列扫描，比较2组肿瘤实质区标准扩散系数（ADC）、真扩散系数（D）、假扩散系数（D*）、灌注分数（f值），采用受试者工作特征曲线（ROC）评价各参数诊断效能。结果普通组标准ADC、D、f值均明显低于黏液性腺癌（P < 0.01）。普通组不同病理分级病人间标准ADC、D、D*、f值差异均无统计学意义（P>0.05）。ROC曲线分析显示，标准ADC、D、f值鉴别诊断普通腺癌和黏液性腺癌的阈值、敏感性、特异性及ROC曲线下面积依次为0.998×10-3 mm2/s、88.3%、55.7%、0.748，0.81×10-3mm2/s、91.7%、72.9%、0.814，43.00%、75.0%、72.9%、0.758。结论IVIM参数能定量反映不同组织学类型直肠癌细胞密集度及灌注特征，其中以D值诊断与鉴别价值最佳，有助于术前预测和治疗方案制定。

Study on the correlation between inteavoxel incoherent motion parameters and histologic type and pathological grade of rectal cancer

ObjectiveTo explore the correlation between inteavoxel incoherent motion(IVIM) parameters and histologic type and pathological grade of rectal cancer.MethodsTwenty-nine patients with common adenocarcinoma of rectum and 12 patients with mucinous adenocarcinoma diagnosed by pathology were divided into the common group and mucinous group, respectively.Two groups were detected using routine MR and IVIM scan(b=0, 10, 20, 50, 100, 200, 400, 800, 1 200, 2 000 s/mm2) before operation.The apparent diffusion coefficient(ADC), true diffusion coefficient(D), pseudo-diffusion coefficient(D*) and perfusion score(f value) were compared between two groups.The diagnostic efficiency of parameters were evaluated using receiver operating characteristic curve(ROC).ResultsThe ADC, D and f value in common group were significantly lower than that in mucinous group(P < 0.01).The differences of the ADC, D and f value in different pathology grades patients in common group were not statistically significant(P>0.05).The results of ROC analysis showed that the optimal threshold value, sensitivity, specificity and area under the curve ROL in common adenocarcinoma of rectum patients and mucinous adenocarcinoma diagnosed by the ADC, D and f value were 0.998×103 mm2/s, 88.3%, 55.7%, 0.748, 0.81×10-3 mm2/s, 91.7%, 72.9%, 0.814, 43.0%, 75.0%, 72.9% and 0.758, respectively.ConclusionsIVIM parameter can quantitatively reflect the characteristics of cell density and perfusion of different histological types of rectal cancer.The D value has the highest diagnostic efficiency, which is helpful for preoperative prediction and making of clinical treatment plans.