直肠癌环周浸润对MRI-T分期诊断价值的临床研究

目的：探讨MRI结合肿瘤侵犯肠壁周径程度在直肠癌T分期中的临床应用。方法：回顾性分析79例直肠癌患者,分别以常规分期、常规分期结合肿瘤侵犯肠周径程度两种方法进行T分期。后者针对低场强MRI鉴别T2期和T3期患者困难时,结合肿瘤侵犯肠壁周径（以肿瘤侵犯肠壁1/2周径为界：〈1/2周径为T2期,≥1/2周径为T3期）进行分期。以术后病理T分期为对照,分析两种方法在评估直肠癌T分期中的应用价值。结果：结合环周径分期和常规分期预测病理T分期的Kappa值分别为0.688和0.331（P〈0.05）。结合环周径分期对直肠癌≤T2期和T3/T4期的诊断参数均优于常规分期方法,前者AUC（ROC曲线下面积）值高于后者（0.905 vs 0.662,P〈0.05）。结论：常规分期结合肿瘤侵犯肠壁周径程度可提高T分期的准确度,尤其是提高T2期和T3期的鉴别,从而为直肠癌多学科诊疗团队（MDT）提供有效的信息。

Demonstration of rectal cancer with the extent of wall invasion as an criteria for improving accuracy of MRI-T staging

Objective： To investigate the value of conventional T staging for rectal cancer and which combined with the extent of tumor invasion of the circumference of rectal wall in T staging for rectal cancer. Methods： The conventional T staging in 79 cases with rectal cancer and that combined with tumor invasion of the circumference of the bowel wall based on MRI were analysed and compared retrospectively. On low field MRI system, when there was difficulty in discriminating stage T2 and stage T3 rectal cancer, then try to find tumor invasion of intestinal wall circumference based on MRI. The cirteria of invasion of bowel wall circumference set for T2 and T3 was 〈1/2-1/2 the circumference was considered as stage T2, 〉1/2 of the circumference as T3. Use postoperative pathologic T staging as standard, the value of conventional T staging and which combined with invasion of the circumference of the rectal wall was compared. Results： Based on conventional T staging and that combined with invasion of the circumference of rectal wall and only conventional T staging, the Kappa pathological T staging values were 0.688 and 0.331 respectively（P〈0.05）. The parameters for stagings≤T2 and T3/F4 based on tumor invasion of rectal circumference in T staging are superior to those based on conventional staging alone, the former AUC（area under the ROC curve） value is higher than the latter （0.905 vs 0.662, P〈0.05）. Conclusion： The conventional T staging for rectal cancer combined with invasion of the circumference of rectal wall can improve the accuracy of T staging for rectal cancer, especially improving the discrimination between T2 and T3 so as to provide effective information for clinicians and surgeons.