肾上腺间质肿瘤的CT、MRI表现及其病理基础

Adrenal Interstitial Tissue Tumors:CT and MRI Findings and Corresponding Pathological Basis

目的分析肾上腺间质肿瘤(AIT)的CT和MRI表现,提高对本病的认识和影像诊断水平。方法回顾性分析17例经手术病理证实的AIT的CT和MRI表现。12例行CT扫描(9例行增强扫描),5例行MRI扫描(2例行增强扫描),其中2例同时行CT及MRI扫描。结果 AIT 17例,其中髓质脂肪瘤10例,脂肪瘤2例,囊性淋巴管瘤2例,畸胎瘤、神经纤维瘤、淋巴瘤各1例。髓质脂肪瘤呈混杂脂肪、骨髓成分密度或信号不均质肿块;脂肪瘤表现为均质的脂肪密度或信号;囊性淋巴管瘤表现为形态特殊的多囊低密度影,较易出现钙化;畸胎瘤CT呈密度不均的肿块,MRI为含多种成分(钙化、脂肪)的混杂信号;神经纤维瘤表现为较低密度肿块,增强扫描轻度强化,MR T1WI上呈低信号,T2WI上呈不均匀高信号;淋巴瘤表现为双侧低密度肿块,增强扫描轻度强化。结论部分AIT具有特征性的CT和MRI表现,术前可做出正确诊断,为临床治疗方案的选择及预后判断提供理论依据。

Objective To analyze CT and MRI features of adrenal interstitial tumor （AIT） in order to make a further understanding of AIT and to improve imaging diagnostic ability. Methods CT and MRI findings of 17 patients with AIT proved by operation and pathology were retrospectively reviewed. Of the 17 eases, CT scan was performed in 12 （including enhanced scanning in 9）, MRI scan in 5 （including enhanced scanning in 2）, and CT together with MRI scan in 2. Re- suits The AIT lesions of the 17 patients included myelolipoma （n = 10） , lipoma （n = 2 ） , cystic adrenal lymphangioma （ n = 2）, teratoma （ n = 1 ）, neurofibroma （ n = 1 ） and lymphoma （ n = 1 ）. On CT and MR images, myelolipoma was char- acterized by marked and mixed fat and marrow density, or a mass with heterogeneous signal intensity. Lipoma was marked by homogenous fat density or signal intensity. Cystic adrenal lymphangioma was manifested as a polycystic mass, and calci- fication was frequently observed. Teratoma displayed as a mixed-density mass on CT and mixed-signal mass on MRI as it contained water, lipoid, calcification, etc. Neurofibroma showed signs of a low-density mass on plain CT images with slight enhancement on contrast-enhanced scanning, while it was hypo-intense on T1WI and hyper-intense on T2WI. As for lym- phoma, it manifested itself as bilateral low-density masses with slight enhancement on contrast-enhanced scanning. Con- clusion Some adrenal interstitial tumors carry characteristic signs on CT and MRI, which can help make a correct diagno- sis before operation. Imaging findings can provide theoretical basis for the selection of clinic therapeutic regimen and for the evaluation of prognosis.