儿童及青少年Xp11.2易位/TFE3基因融合相关性肾癌的CT表现与病理对照分析

Comparative CT imaging findings and pathological features of Xp11.2/TFE3 translocation renal cell carcinoma in children and adolescents

目的分析儿童及青少年Xp11.2易位/TFE3基因融合相关性肾癌(Xp11.2易位性肾癌)CT与病理相关性,总结该病的CT诊断要点。方法选取并分析病理确诊的5例儿童及青少年Xp11.2易位性肾癌的CT特征,包括肿瘤的位置、大小、形态、密度、成分、强化方式及程度、转移情况,并对照病理改变分析CT影像特点与组织学间的关系。电话随访患者预后。结果5例患者右肾3例,左肾2例,均为单肾单发。其中皮髓质型3例,髓质型与皮质型各1例。CT特征均反映了相应的病理学改变。CT平扫5例肿瘤的实质部分均表现为略高密度;4例表现为类圆形肿块,1例表现为不规则肿块;5例含有囊变/坏死,3例含有钙化,1例含有脂肪;4例突破肾包膜,3例发生转移;增强扫描3例呈“快进慢出”型,1例呈“少进慢出”型,1例呈“无显著变化”型。4例肿瘤可见延迟强化的包膜。所有患者临床症状均无特异性。随访至2021年11月,除1例患者死亡外,其余4例预后良好。结论儿童及青少年Xp11.2易位/TFE3基因融合相关性肾癌具有一定的CT影像学特征,当肿瘤内部出现囊变/坏死、钙化,CT平扫时呈略高密度,动态增强轻中度延迟强化并可见延迟强化的包膜时,需考虑该疾病。

Objective To summary the CT features of Xp11.2/TFE3 translocation renal cell carcinoma in children and adolescents through analyzing the relationship between CT imaging findings and pathological features of the tumor.Methods CT images,pathological and clinical data of 5 children and adolescents with Xp11.2/TFE3 translocation renal cell carcinoma were collected.The tumor location,size,shape,density,composition,enhancement pattern and metastasis were recorded.The relationship between histological features and imaging findings were analyzed.Follow-up visits were conducted to obtain information of survival outcome.Results Among the 5 patients,1 patient died,and 4 patients remained alive till the endpoint of our follow-up.Three tumors were located in the right kidney,and two tumors were in the left.Three tumors were cortical-medullary type,one tumor was cortical type and one tumor was medullary type.The CT features were correlated with pathological changes.Four of 5 tumors were round-like mass,One of 5 tumors were irregular mass.Five of 5 tumors were mildly hyperdense in plain scan imaging.Five of 5 tumors were accompanied with cystic component/necrosis,3 of 5 with calcification,1 of 5 with fat.Four of 5 presented with renal capsule disruptionand,and 3 of 5 with metastasis.On enhanced CT images,3 tumors showed“fast in slow out”enhancement,and 1 tumor showed“less in slow out”enhancement,1 tumor showed no change on the three phases.ConclusionXp11.2/TFE3 translocation renal cell carcinoma has certain imaging features.When the renal tumor in children and adolescents showed necrosis,calcification,and showed mildly hyperdense on unenhanced CT scan,moderate enhancement during the corticomedullary phase and delayed enhancement during the nephrographic phase and excretory phase,the Xp11.2/TFE3 translocation renal cell carcinoma should be considered.