DWI对低位直肠癌术前T分期的评估价值及与Ki-67表达的相关性

Value of DWI in assessing preoperative T staging of low rectum cancer and correlated with expression of Ki-67

目的 探讨弥散加权成像(DWI)所得ADC值对低位直肠癌术前T分期的评估价值及与Ki-67表达的相关性。方法 回顾性分析87例经手术病理证实为低位直肠癌患者的资料。所有患者在术前两周内完成MRI检查,并获得ADC值。分析ADC值与手术病理T分期的相关性。应用免疫组化检测肿瘤标本的Ki-67表达,分析ADC值与Ki-67增殖指数之间的相关性。结果 所有直肠癌病灶ADC值范围为(0.6-1.2)×10^-3mm^2/s,肿瘤组织Ki-67增殖指数平均为(55.3±20.2)%;肿瘤ADC值与病理T分期呈负相关(r=-0.68,P<0.01);ADC值与Ki-67增殖指数也呈负相关(r=-0.63,P<0.01)。结论 ADC值与低位直肠癌术前T分期具有较好的相关性,对肿瘤的生物学行为判定有较高的价值,可以作为直肠癌侵袭性的潜在影像生物标记。

Objective To study the value of Diffusion-weighted imaging (DWI) in assessing preoperative T staging of low rectum cancer and correlated with expression of Ki-67. Methods Data on 87 patients with a proven pathology of low rectal cancer were retrospectively analyzed. All patients underwent an MRI scan two weeks prior to operation, and the mean ADC value was measured. The correlation between ADC value and T staging features was studied. Ki-67 expression was determined using immunohistochemical method in all patients. The correlation between Ki-67 expression and ADC features was studied. Results The ADC value of all tumors ranged from 0.60 ×10 ^-3 mm^ 2/sto 1.20×10 ^-3 mm ^2/s. The average Ki-67 proliferation index was 55.3 ± 20.2%. Negative correlation was observed between preoperative ADC vaule and pathological T staging of low rectal cancer ( r =-0.68, P <0.01). Negative correlation was observed between preoperative ADC vaule and Ki-67 proliferation index of rectal cancer ( r =-0.63, P <0.01). Conclusion There is a good correlation between ADC value and T staging of low rectum cancer. ADC values may facilitate evaluation of the biological behavior of low rectal cancer. ADC values should be considered a sensitive image biomarker of rectal cancer.