MRI对子宫内膜癌组织学分级的价值研究

The value of MRI in the histological grading of endometrial cancer

目的探究磁共振成像(MRI)对子宫内膜癌组织学分级的价值。方法回顾性分析首都医科大学附属北京世纪坛医院2017年至2020年经手术证实的64例子宫内膜癌患者的MRI图像,分别在横轴位与正中矢状面测量肿瘤及子宫的最大左右径、前后径及头足径,根据简化的椭球体积公式计算出肿瘤及子宫体积并计算两者比值(N/U)。以病理学所见为金标准,应用非参数检验(Kruskal⁃Wallis检验)与单因素方差分析比较不同组织学级别(G1、G2、G3)子宫体积、肿瘤体积及N/U的差异。根据肿瘤浸润肌层深度与5年生存率将G1、G2、G3肿瘤分为高级别组与低级别组。应用受试者操作特征曲线(ROC曲线)分析两个组别的N/U在术前预测肿瘤组织学分级中的价值。结果64例子宫内膜癌中G1级20例,G2级24例,G3级20例,三组之间肿瘤体积差异无统计学意义(H=3.528,P=0.171)。G1级、G2级及G3级肿瘤的N/U值分别为(0.13±0.07)、(0.19±0.06)和(0.21±0.08),三者间差异具有统计学意义(F=9.04,P<0.01)。高级别组与低级别组差异无统计学意义。以N/U值0.16为截断值区分G1肿瘤和G2/G3肿瘤,其曲线下面积(AUC)为0.80,敏感度为79.5%,特异度为80%。结论MRI对子宫内膜癌组织学分级具有一定诊断价值。

Objective To investigate the value of magnetic resonance imaging(MRI)in the histological grading of endometrial cancer.Method MR images of 64 patients with endometrial cancer confirmed by surgery from 2017 to 2020 were analyzed retrospectively from Beijing Shijitan Hospital Capital Medical University.The maximum left and right diameter,anterior and posterior diameter and head and foot diameter of tumor and uterus were measured on the maximum display level of the tumor and the median sagittal plane of the image respectively.According to the simplified ellipsoid volume formula,the volume of tumor and uterus was calculated and their ratio neoplasm/uterus(N/U)was calculated,taking pathological findings as the gold standard,the differences of uterine volume,tumor volume and N/U at different histological grades(G1,G2 and G3)were compared by Nonparametric test(Kruskal⁃Wallis test)and one⁃way ANOVA.According to the depth of tumor invasion and 5⁃year survival rate,G1,G2 and G3 tumors were divided into high⁃grade group and low⁃grade group.Receiver operating characteristic curve(ROC curve)was used to analyze the value of N/U in different group in predicting the histological grade of tumor before operation.Result Among the 64 cases of endometrial cancer,there were 20 cases of G1 grade,24 cases of G2 grade and 20 cases of G3 grade.There was no significant difference in tumor volume among the three groups(H=3.528,P=0.171).The N/U values of G1,G2 and G3 tumors were(0.13±0.07),(0.19±0.06),(0.21±0.08),respectively.The difference among the three groups was statistically significant(F=9.04,P<0.01).There was no statistically significant between high⁃grade group and low⁃grade group.Distinguishing G1 tumors from G2/G3 tumors with the cutoff value of 0.16,the area under curve(AUC)was 0.80,the sensitivity was 79.5%and the specificity was 80%.Conclusion MRI has certain diagnostic value for histological grading of endometrial cancer.