肺硬化性血管瘤的超微结构观察

Ultrastructural observation of sclerosing hemangioma of the lung

肺硬化性血管瘤 (sclerosinghaemangioma ,SH)是一种少见的良性肿瘤。瘤组织主要由表面细胞和多角形细胞两种细胞类型组成 ,但其组织发生一直存在争议。本文收集 6例肺SH病例 ,着重对其超微结构进行了细致的观察 ,并结合其光镜及免疫组化 (CK、EMA、TTF 1、CgA及SyN)等结果进行了分析。结果显示 ,6例SH中 5例为女性 ,组织学可见乳头区、硬化区、实性区和出血区四种结构。电镜下表面细胞表面见不等量的短的微绒毛 ,胞浆中细胞器较丰富 ,可见发达的粗面内质网及多量线粒体 ;多角形细胞电镜下多为亮细胞 ,胞浆空淡 ,见散在的细胞器 ;瘤细胞内可见不等量的电子致密小体 ,直径 0 3～ 1 2 μm不等 ,未见明显的分泌颗粒及板层小体。 6例SH中CK、EMA和TTF 1均为 1 0 0 %阳性表达。CgA和SyN在 5例SH为阴性 ,仅 1例SH在实性区有少量散在的阳性。提示SH起源于原始呼吸道上皮 ,而CK和EMA在这两种细胞表达的差异可能代表了它们不同分化的差异。

Sclerosing hemangioma (SH) of the lung is an uncommon benign tumor of uncertain histogenesis that is composed of two major cell types: surface and polygonal cells. 6 cases of SH were observed with electron microscope and analyzed in conjunction with its histopathologic and immunohistochemical( CK,EMA,TTF 1, CgA and SyN) observations. SH presented as a predilection for woman (5/6) and showed four distinct patterns (papillary, sclerotic, solid and hemorrhagic) with a variable proportion. Ultrastructural observation showed that the surface cells with variable short microvilli have the greater number of cytoplasmic organelles including abundant rough endoplasmic reticulum and mitochondria. Polygonal cells have lighter cytoplasm with sparse organelles. Variable electron dense bodies of different sizes (range, 0.3～1.2μm) and shapes were present. Obvious secretory granules and osmophilic lamellar bodies were not shown. There were 100% positive for CK, EMA and TTF 1 expression. CgA and SyN were predominantly negative despite a few of scatter positive cells in solid areas of 1 case. It was suggested that SH is an epithelial neoplasm derived from primitive respiratory epithelium. The different expressions of CK and EMA on surface and polygonal cells may present variable differentiation from a progenitor cell. Few of tumor cells may have the differentiation of clara cells.