卵巢纤维卵泡膜瘤的MRI表现

MRI Features of Ovarian Fibrothecomas

目的:分析卵巢纤维卵泡膜瘤的MRI表现,以提高对其MRI特征的认识。方法:回顾分析20例经病理证实的卵巢纤维卵泡膜瘤的MRI表现及临床资料。根据T2WI信号特点将病例分成高信号组与低信号组,采用t检验及精确Fisher确切概率法比较两组间肿瘤最大径、血清糖抗原125(CA-125)升高例数以及子宫内膜病变发生例数之间的统计学差异。结果:20位患者中18例为绝经后妇女(90%),10例(50%)表现为CA-125增高,6例(30%)合并子宫内膜病变,1例(5%)合并卵巢畸胎瘤。20例患者均出现腹水体征,其中1例表现中等量腹水,19例为少量腹水。T1WI上所有肿块都表现为略低信号。肿瘤的T2WI有两个主要特点:(1)以等、稍高信号为主(稍高信号组,10例)。(2)以低信号为主(低信号组,10例)。两组间病灶最大径、CA-125值升高例数差异无统计学意义,P=0.439、P=0.656;两组间子宫内膜病变发生数差异有统计学意义(P=0.011)。增强后肿瘤呈轻度、不均匀强化,强化程度小于子宫肌层(P=0.000)。结论:良性肿瘤的形态学特征、少血供、T2WI信号、常合并腹水及子宫内膜病变的MRI特征有助于卵巢纤维卵泡膜瘤的诊断。肿瘤的T2WI信号特点有助于患者高雌激素血症的诊断。

Purpose： To analyze the MRI appearances of fibrothecomas and to improve the diagnosis of the disease. Methods： MRI appearances of 20 cases ovarian fibrothecomases confirmed by surgical pathology results were retrospectively reviewed and correlated with clinical findings. All cases were divided into hyper-intensity and hypo-intensity groups based on their T2WI characteristics. T test and Fisher precise probabilistic method were used to analyze the difference of maximum diameter, numbers of serum carbohydrate antigen 125 （CA-125） abnormality and numbers of endometrial abnormality between the two groups. Results： Most patients were post-menopausal females （18/20, 90%）. Ten patients （10/20, 50%） showed with an elevated CA-125 level, 6 （6/20, 30%） showed with endometrial abnormality. All cases were accompanied with ascites, and 5% （1/20） patients with teratoma of ovary. On Tl-weighted imaging, all the fibrothecomas were shown as homogeneous hyper-intensity masses. On T2-weighted imaging, 2 distinct features were revealed： （1） Heterogeneous tumors with mostly iso-intensity and few patchy hyper- intensity areas in 50% （10/20） cases; （2） Heterogeneous tumors with predominantly hypo-intensity in 50% （10/20） cases. There was no statistical significant difference among the T2-weighted image features （P=-0.925, 0.656） in terms of the CA-125 levels, size of fibrothecomas. There was statistical significant difference among T2-weighted image features （P=0.011） in terms of the endometrial abnormality. On post-contrasted images, all tumors showed homogeneous mild enhancement, which was less than that of myometrium. Conclusion： The morphological features of benign solid tumor, less blood supply, character signal on T2WI, complicating with ascites, elevated serum CA-125 levels and endometrial abnormality play an important role in the diagnosis of fibrothecomas. The features of T2WI characteristics might be helpful in diagnosis of the immunohistochemical aspects.