MRI特征术前预测儿童髓母细胞瘤危险度分组的研究

Preoperative prediction of risk groups for medulloblastoma in children with MRI features

目的分析儿童髓母细胞瘤(MB)的MRI特征,筛选术前预测MB危险度分组的征象。方法回顾性分析2012年12月至2021年12月深圳市儿童医院经病理证实62例MB患儿的临床及影像资料。参照儿童MB诊疗规范(2021年版)将其分为标危组(43例)和高危组(19例)。观察并记录MB的MRI征象,包括肿瘤部位、中心位置、肿瘤形态、T_(1)WI、T_(2)WI及DWI信号强度、强化方式、囊变大小、囊变位置、囊变数量、瘤周水肿、脑积水,并测量肿瘤最大径。采用χ^(2)检验或Fisher确切概率法比较标危组与高危组间年龄、性别、MRI征象的差异,采用独立样本t检验比较2组间肿瘤最大径的差异,将组间差异有统计学意义的指标纳入二元logistic回归分析,得出危险度分组的独立影响因素,并采用受试者操作特征曲线评价其诊断效能。结果标危组与高危组MB间年龄(P=0.026)、强化方式(P=0.018)、囊变大小(P=0.005)、囊变位置(P=0.011)、囊变数量(P=0.003)的差异有统计学意义,性别、肿瘤部位、肿瘤中心位置、肿瘤形态、T_(1)WI、T_(2)WI及DWI信号强度、瘤周水肿、脑积水、肿瘤最大径差异均无统计学意义(P>0.05)。二元logistic回归结果示,年龄(OR为0.207,95%CI 0.040~0.983,P=0.042)、囊变数量(OR为0.215,95%CI 0.073~0.630,P=0.005)是高危组MB的独立保护因素,而强化方式Ⅲ型(OR为5.226,95%CI 1.516~52.920,P=0.048)是高危组MB的独立危险因素,3个指标联合诊断高危MB的曲线下面积为0.845(95%CI 0.741~0.949)。结论年龄和MRI征象肿瘤强化方式Ⅲ型、囊变数量可用于术前预测MB危险度分组。当患儿年龄较小、MB强化方式以肿瘤周边强化为主且无明显囊变时,可能提示为高危MB。

Objective To analyze the MRI features of medulloblastoma(MB)in children,and screen out the key signs that can predict the risk of MB before surgery.Methods Clinical and radiological data of 62 children with MB confirmed by pathology in Shenzhen Children′s Hospital from December 2012 to December 2021 were retrospectively analyzed.According to the diagnosis and treatment guidelines for children with MB(2021 edition),the patients were divided into standard risk group(43 cases)and high risk group(19 cases).MRI features of MB were observed and recorded,including tumor site,location of tumor center,tumor morphology,signal intensity of T_(1)WI,T_(2)WI and diffusion weighted imaging(DWI),enhancement pattern,cystic lesion size,location and number,peritumoral edema and hydrocephalus,and the maximum diameter of tumor was measured.Theχ^(2) test or Fisher exact probability method was used to compare the differences in age,gender and MRI signs between the two groups.The t test of two independent samples was used to compare the differences in the maximum diameter of tumors between the two groups.The indicators with statistically significant differences were included in binary logistic regression analysis to obtain independent influencing factors associated with the risk groups.The receiver operation characteristic curve was used to evaluate the diagnostic efficacy.Results There were significant differences in age(P=0.026),enhancement pattern(P=0.018),cystic lesion size(P=0.005),location(P=0.011)and number(P=0.003)between standard risk group and high risk group.There were no significant differences in gender,tumor site,location of tumor center,tumor morphology,signal intensity of T_(1)WI,T_(2)WI and DWI,peritumoral edema,hydrocephalus and maximum diameter of tumor between the two groups(P>0.05).Binary logistic regression results showed the age(OR=0.207,95%CI 0.040-0.983,P=0.042)and the number of cystic lesions(OR=0.215,95%CI 0.073-0.630,P=0.005)were the protective factors for MB in high risk group,the enhancement patternⅢ(OR=5.226,95%CI 1.516-52.920,P=0.048)was the dangerous factor for MB in high risk group.The area under the curve of the combined diagnosis of high risk MB was 0.845(95%CI 0.741-0.949).Conclusions The age and MRI signs the pattern of tumor enhancementⅢand the number of cystic lesion can be used to predict the risk grouping of MB preoperatively.When the child is younger and MB enhancement pattern is mainly peripheral enhancement without obvious cystic change,it may indicate high risk MB.