树突状纤维黏液脂肪瘤10例临床病理分析

Dendritic fibromyxolipoma:a clinicopathologic analysis of 10 cases

目的探讨树突状纤维黏液脂肪瘤(dendritic fibromyxolipoma,DFML)的临床病理学特征和鉴别诊断。方法回顾性分析10例DFML的临床资料、病理学形态和免疫表型,并复习相关文献。结果男性9例,女性1例,年龄39～67岁,平均54岁。多发生于颈项部和肩背部,表现为皮下缓慢性生长的无痛性肿块,直径1～6 cm,平均3.6 cm。肿瘤周界清晰或有菲薄包膜,切面呈灰黄至灰白色,黏液样。镜下见肿瘤由增生的小梭形至星状纤维母细胞样细胞、多少不等的成熟脂肪细胞和黏液样基质组成,细胞之间可见绳索样或纤细的胶原纤维,肿瘤内偶可见丛状小血管,间质内含有少量散在的肥大细胞。免疫组化标记小梭形和星状纤维母细胞样细胞表达vimentin、CD34和BCL-2,其中标记vimentin和CD34可清晰显示树突状的胞质突起。结论 DFML是一种好发于中老年男性的特殊亚型脂肪瘤,与梭形细胞脂肪瘤关系密切,可能属于梭形细胞脂肪瘤的黏液样变型。其需与其他黏液样肿瘤相鉴别。

Purpose To investigate the clinicopathological characteristics of dendritic fibromyxolipoma （DFML） and to discuss the dif- ferential diagnosis. Methods The clinical, pathological and immunophenotypic features in l0 cases of DFML were analyzed. The lit- eratures were reviewed. Results Nine patients were male and l was female with age ranging from 39 - 67 years （ mean, 54 years）. The tumor presented as a slowly growing subcutaneous nodule with a predilection for the posterior neck, back and shoulder. They were well circmnscribed or encapsulated, measuring in size from 1 to 6 cm （ mean, 3.6 cm） with yellowish to gray in color and myxoid ap- pearance on cut surface. Histologically, the tumor was composed of small spindle to stellate fbroblasts intermixed with rope-like or slender collagen fbers and varying amount of mature lipocytes embedded in a myxoid stroma. A few scattered mast cells were seen. By immunohistochemistry, tumor cells expressed vimentin, CD34 and BCL-2. In particular, the vimentin and CD34 expression accentua- ted the dendritic phenotype of the cyoplasmic processes. Conclusions DFML is a special variant of lipoma with a predilection for mid- die to old aged males. The overlapping features between DFML and spindle cell lipoma suggest that they lie within the same spectrum of a single entity. Awareness of this rare tumor type is helpful in the differential diagnosis from a variety of other myxoid tumors.