肺外炎性肌纤维母细胞瘤的影像学表现

The imaging of extrapulmonary inflammatory myofibroblastic tumor

目的分析肺外炎性肌纤维母细胞瘤的影像学表现,提高对该病的认识。方法搜集经手术病理确诊的肺外炎性肌纤维母细胞瘤6例,其中5例行免疫组织化学检查。6例均行CT检查,其中4例行CT增强,1例行MRI平扫+增强检查,回顾性分析其影像学表现特点。结果 6例病灶均单发,分别位于胸膜、右下腹、脾、肝、声带、下颌。CT表现:1例位于声带仅表现为声带稍增厚,其余5例均见软组织肿块,边界尚清,形态尚规则,轻中度强化。脾内病灶可见液化坏死无强化区。右下腹病灶MRI表现为T1WI等信号,T2WI稍低信号,DWI明显高信号。病理示瘤组织由梭形纤维细胞组成,伴大量炎性细胞浸润,免疫组化SMA阳性表达。结论炎性肌纤维母细胞瘤影像学表现无特异性,确诊仍需病理学检查,但影像学检查可显示病灶本身及周围情况,对患者预后及随访有一定作用。

Objective To analyze the imaging of extrapulmonary inflammatory myofibroblastic tumor（ IMT） and to improve the knowledgement of it. Methods 6 cases of IMT were confirmed by pathology,in which 5 cases underwent immunohistochemistry examination. The imaging appearances were retrospectively discussed. Results All cases were solitary and occured in pleura,right lower quadrant,spleen,liver,vocal cord and underjaw,respectively. 6 cases underwent CT scan and 4 cases underwent enhanced scan. 1 case underwent MRI plain and contrast scan. CT demonstrated soft tissue mass in 5 cases with well defined boundary,regular shape and slight or moderate enhancement. 1 case demonstrated slightly thick vocal cord. Necrosis without enhancement can be seen in the center of spleen IMT. The right lower quadrant lesion appeared equal signal on T1 WI,lower signal on T2 WI,and high signal on DWI. The tumor tissue consisted of spindle fiber cells with a large amount of inflammatory cell infiltration. SMA expressed positively on immunohistochemistry. Conclusion IMT appeared no specificity in imaging,pathology should be done to confirm it. But,imaging can reveal the lesion itself and relationship to the surrounding tissue. It has a certain value in prognosis and follow-up.