脾窦岸细胞血管瘤2例临床病理观察

Littoral cell angioma of spleen:a clinicopathologic analysis of two cases

目的探讨脾窦岸细胞血管瘤(LCA)的临床病理及相关性、免疫表型特征、诊断与鉴别诊断要点。方法对2例脾LCA进行临床资料、影像学特征及病理形态学分析,进行多种免疫组化标记,并复习相关文献。结果 2例脾LCA有相似的临床表现(脾大、脾功能亢进),CT示脾实质内多发及单发性低密度影,增强扫描有对比增强表现。2例大体病理均为脾不同程度增大,例1脾实质内有多个暗红色结节;例2为单发结节,并伴多发性肾囊肿病、肝囊肿。2例镜下改变均为瘤组织由大小不等的窦样腔隙构成,腔壁向腔内形成乳头状结构,少数呈囊状扩张,内衬单层内皮样细胞。这些细胞有两种类型,一类内衬细胞呈高柱状,具有巨噬细胞/组织细胞样形态,体积较大,部分游离在腔内呈稀疏片状;另一类内衬细胞形似正常窦岸细胞,体积较小;两类细胞无明显异型。2例LCA大细胞CD68/kp1、CD163和溶菌酶(+),少数大细胞CD31(+),CD34(-);2例小细胞CD31、多克隆第Ⅷ因子相关抗原和CD21(+),CD8弱(+)/(-),CD34(-),组织细胞抗原均(-)。大、小细胞S-100、单克隆FⅧAg均(-)。结论 LCA是一种较为罕见的良性病变,特征性的病理形态改变及CD31、多克隆FⅧ抗原和组织细胞抗原的检测有利于诊断,应密切随访,以除外肿瘤复发及伴发恶性肿瘤可能。

Objective To study the clinicopathologic features,immunophenotype,and the main points of diagnosis of splenic littoral cell angioma.Methods The clinical features,radiologic findings and histopathologic changes were analyzed in 2 cases of splenic littoral cell angioma.Immunohistochemical study was carried out on paraffin-embedded tissues,and relevant literatures were reviewd.Results All the 2 cases had similar clinical manifestations and radiologic findings,namely splenomegaly and hypersplenism.CT showed multiple and single splenic shadows with low density,enhanced scans resulting in contrast-enhanced performance.Gross examination revealed an enlarged spleen.The splenic parenchyma in the first case showed multiple dark red nodules,while the second case had a singe nodule with multiple renal cysts and liver cysts.Histologically,the lesions consisted of anastomosing ascular channels with papillary and few had cavernous appearance.Two types of cells were identified： one columnar lining cells were large with macrophages/cell-like morphology,part of the free sheet in the cavity was sparse;the other,resembled a normal lining littoral cells,were small.The two types of cells showed no significant atypia.Immunohistochemisty showed that large cells in the two cases of LCA were positive for CD68 /kp1,CD163,lysozyme,etc,a few of them expressed CD31,but no expression of CD34;small cells expressed CD31,polyclonal section Ⅷ factor related antigen and CD21,CD8 weak positive or negative,CD34 negative,and histocytic antigens were negative.Large and small cells did not expressed in S-100 protein and monoclonal F ⅧAg.Conclusions LCA is a rare benign lesion.Characteristic pathological changes and the expression of CD31,polyclonal FⅧAg and histocytic antigens are helpful to the diagnosis of LCA.LCA cases should be closely followed up,in order to rule out tumor recurrence and a second visceral malignancy.