应用相对表观扩散系数评估膀胱癌侵袭性及增殖性的初步研究

Preliminary Study on the Application of Relative Apparent Diffusion Coefficient to Assess the Invasiveness and Proliferation of Bladder Cancer

目的探讨相对表观扩散系数(rADC)值和表观扩散系数(ADC)值对膀胱癌肌层侵袭性的诊断价值,并评估两者与肿瘤增殖性指标(Ki-67)表达水平之间的相关性。方法106例经病理证实的尿路上皮癌患者,术前行常规MRI及DWI检查。测量病灶ADC值,并以闭孔内肌及臀大肌作参照,分别计算rADC1及rADC2。比较肌层浸润性膀胱癌(MIBC)组和非肌层浸润性膀胱癌(NMIBC)组的rADC值与ADC值的差异;并评估两者与Ki-67表达水平之间的相关性。结果MIBC组的ADC值、rADC1及rADC2分别为(0.97±0.22)×10^(-3)mm^(2)/s、(0.58±0.14)×10^(-3)mm^(2)/s、(0.64±0.15)×10^(-3)mm^(2)/s,显著低于NMIBC组ADC值、rADC1、rADC2[分别为(1.23±0.25)×10^(-3)mm^(2)/s、(0.81±0.16)×10^(-3)mm^(2)/s、(0.87±0.19)×10^(-3)mm^(2)/s],P值均<0.001。ADC值为1.165×10^(-3)mm^(2)/s时,敏感性为81.3%,特异性为74.6%;rADC1为0.767时,敏感性和特异性分别为86.1%、83.5%;rADC2为0.851时,敏感性和特异性分别为84.7%、78.4%。rADC值和ADC值均对膀胱癌肌层侵犯有诊断价值,且rADC值的诊断效能优于ADC值。rADC值及ADC值均与Ki-67表达均呈负相关(r1=-0.509、r2=-0.467、r=-0.339,P值均<0.001),且rADC值与Ki-67指标之间相关性更高。结论rADC值有助于评估膀胱癌侵袭性,并一定程度上反映肿瘤细胞增殖性,为患者术前肿瘤分期提供一定依据。

Objective Toinvestigate the diagnostic value of relative apparent diffusion coefficient(rADC)and apparent diffusion coefficient(ADC)on the invasiveness of bladder cancer myometrium,andevaluate the correlationbetweenrADC/ADC and the expression of tumor proliferation index(Ki-67).Methods 106 patients with urothelial carcinoma confirmed by pathology were examined by routine MRI and DWI before operation.The ADC value of each lesion was measured,and the obturator internus muscle and the gluteus maximus muscle were used as the reference site to calculate the rADC1 and rADC2.The differences of rADC/ADC value between the muscular invasive bladder cancer(MIBC)group and the non-muscle invasive bladder cancer(NMIBC)group were analyzed.The correlations between rADC/ADC value and Ki-67 expression were also evaluated.Results The ADC values、rADC1 and rADC2 of the MIBC group were 0.97±0.22×10^(-3)mm^(2)/s,0.58±0.14 and 0.64±0.15,which were significantly lower than those of the NMIBC group(1.23±0.25×10^(-3)mm^(2)/s,0.81±0.16,0.87±0.19,P<0.001 respectively).Whenthe cutoff value of ADC was 1.165×10^(-3)mm^(2)/s,the sensitivity and specificity were 81.3%and 74.6%;when the cutoff value of rADC1 value was 0.767,the sensitivity and specificity were 86.1%,83.5%,respectively.Whenthe cutoff value of rADC2 value was 0.851,the sensitivity and specificity were 84.7%,78.4%,respectively.Both rADC value and ADC value had diagnostic value for muscular invasion of bladder cancer,and the diagnostic efficiency of rADC value was better than ADC value.The rADC value and ADC value were negatively correlated with the expression of Ki-67(r1=-0.509,r2=-0.467,r=-0.339,P<0.001 respectively),and the correlation between the rADC value and the expression of Ki-67 was higher.Conclusion The rADC value was helpful to evaluate the invasiveness of bladder cancer,and it could reflect the proliferation of tumor cells to a certain extent,which provides certain basis for the preoperative tumor staging of patients.