腹膜后单中心型Castleman病的CT表现及其强化特征分析

CT findings and enhancement characteristics of retroperitoneal unicentric Castleman’s disease

目的分析腹膜后单中心型Castleman病(UCD)的增强CT特征,提高对本病影像表现的认识。方法回顾性分析经手术病理证实的15例(透明血管型10例,混合型5例)腹膜后UCD病人的CT表现;男10例,女5例,中位年龄29岁。观察病灶的部位、形态、边缘、有无钙化、强化特点、病灶周围有无异常血管及卫星灶。测量平扫、动脉期及静脉期病灶和肾皮质的CT值并计算病灶与肾皮质相对强化率。采用Mann-Whitney U检验比较2种病理类型病灶与肾皮质相对强化率。结果腹膜后UCD的CT主要征象为位于肾脏周围(10例,66.7%)、肾形样轮廓(9例,60.0%)、边缘“晕征”(11例,73.3%)、病灶内钙化(7例,46.7%)。12例行增强扫描病例中可见病灶内低强化区(7例,58.3%)、病灶内异常血管(11例,91.7%)及周围卫星灶(8例,66.7%);有11例病灶在动脉期明显强化,其中6例在静脉期表现为强化略减低,5例为持续或进一步强化;另外1例病灶在各期均表现为轻度强化。本组病灶在增强扫描各期的CT值均低于肾皮质,动脉期和静脉期2种病理类型病灶与肾皮质相对强化率差异均无统计学意义(均P>0.05)。结论腹膜后UCD的增强CT表现具有一定特征,认识这些影像特征有助于提高诊断水平。

Objective To analyze the imaging features of retroperitoneal unicentric Castleman’s disease(UCD)on contrast-enhanced CT,and to improve the recognition of this disease.Methods CT features of 15 patients,including 10 males and 5 females,with a median age of 29 years,were analyzed retrospectively and pathologically confirmed retroperitoneal UCD(10 cases of hyaline vascular type,5 cases of mixed type).Lesion location,shape,edge,calcification,enhancement characteristics,abnormal blood vessels and satellite lesions around the UCD were evaluated.CT values of the lesions and the renal cortexes were measured at pre-enhanced,arterial,and venous phases,and the relative enhancement rates of the lesions and the renal cortexes were calculated.Mann-Whitney U test was used to comparing the difference in relative enhancement rate between the two pathological types for the lesions and the renal cortexes.Results The main signs on CT scan of retroperitoneal UCD included location around the kidney(10 cases,66.7%),kidney-like outline(9 cases,60.0%),“halo sign”of margin(11 cases,73.3%),and calcification(7 cases,46.7%).Low enhancement area in the lesion(7 cases,58.3%),abnormal blood vessels(11 cases,91.7%),and satellite lesions(8 cases,66.7%)around the lesion were presented in 12 patients with contrast-enhanced CT scan.Following intravenously administration of contrast agent in the 12 patients,11 lesions were significantly enhanced at the arterial phase,of which 6 lesions showed slightly decreased enhancement,while the other 5 lesions showed persistent or further enhancement at the venous phase.The other one lesion presented mild enhancement at both the arterial and venous phases.The CT values of the lesions were lower than those of renal cortexes at two phases on contrast-enhanced CT scan.For the lesions and the renal cortexes,there was no statistically significant difference in the relative enhancement rate between the two pathological types of UCD at the arterial and venous phases(P>0.05).Conclusion Retroperitoneal UCD presents several characteristics on contrast-enhanced CT scans,and the recognition of these imaging features could improve the diagnostic level.