皮下组织膜状脂肪坏死误诊3例并文献复习

Mis-diagnosis of membranous fat necrosis in subcutaneous tissue: a report of 3 cases and review of literature

目的对膜状脂肪坏死的病理特征、诊断要点及其鉴别进行探讨。方法观察3例皮下组织膜状脂肪坏死的病理形态学改变,经多种免疫组化标记、特染并文献复习。结果3例的病理学变化为:皮下脂肪组织陈旧性坏死,吞噬细胞吞噬坏死物,成为泡沫细胞,进一步形成早、中、晚期膜状脂肪坏死的囊膜状结构及周围炎症性反应性增生。膜状物免疫组化CD68(+),Vim、S-100、HMB45、CD1a、EMA和CK(-)。特染PAS(+),Masson染色呈红色至金黄色、网状纤维延伸到囊膜腔面以及富于嗜银颗粒。膜状物及泡沫细胞呈自发黄绿色荧光。结论膜状脂肪坏死是一种特殊类型的陈旧性脂肪坏死性炎症。可能因坏死脂肪被吞噬而发生化学变化,形成特殊的膜状结构。诊断依靠其独特的病理形态学改变,并结合免疫组化及特染检测。

Objective To investigate the histopathological characteristics diagnostic criteria and differential diagnosis of membranous fat necrosis （MFN）. Methods Three cases of MFN were studies by histopathological changes, immunohistochemistry, special dyeing as well as literature review. Then analysis histopathological characteristics and the reason of mis-diagnosis. Results The histopathological changes were observed in 3 cases of MFN： a background of subcutaneous fat necrosis, macrophages licked up necrosis to foam cells, developping the cyst and cystic membranes. Cystic membranes were stained by CD68, PAS, Masson; not by VIM, S-100, HMB45, CDla, EMA, and CK. Reticulation fibrin reached to surface of the membranous and abound in argentums granule. There was autofluorescence of the membranes by fluorescent microscope examination of unstaincd sections. Conclusions The MFN is a special inflammation. The fat phagocytosis causes histochemical changes, then becomes the special MFN. The histopathological characteristics, immunohistochemistry and special staining studies are the diagnostic basis for MFN.