涎腺粘液表皮样癌的病理分析

观察18例粘液表皮样癌(12例发生于腮腺,6例发生于小涎腺)的病理学改变。按实体性上皮团与粘液腺管的比例瘤组织可分三种类型:1. 粘液腺管为主型(4例);2. 实体性上皮团为主型(4例);3. 粘液腺管与实体性上皮团混合型(7例);4. 特殊型(3例)。透射电镜观察2例的中间型细胞,胞浆中或有分泌物前体,或有成熟的分泌颗粒;有的细胞内有多量张力细丝;细胞间或见桥粒,或有发育不良的细胞连接。以上发现表明中间型细胞是一种具有向棘细胞和腺细胞双向分化能力的低分化瘤细胞。在4例中观察到较大导管上皮由单纯增生、异常增生过渡到癌的形态学表现,一例见癌旁导管上皮异型增生。这5例癌的组织学类型3例为实体上皮团为主型,2例为实体性上皮团与粘液腺管混合型。

PATHOLOGIC ANALYSIS OF MUCOEPIDERMOID CARCINOMA IN SALIVARY GLAND

Histopathological appearance of 18 cases of mucoepider-moid carcinoma was reviewed,among which 12 cases were in parotidglands and 6 cases in minor salivary glands.According to the propor-tions of solid epithelial mass to the mucous gland there are 3 types:1. mucous gland predominance(4 cases);2. solid epithelial mass predo-minance(4 cases);3. mixed mucous gland and solid epithelial mass,and 4. miscellaneous type.Intermediate cells in 2 cases have been obser-ved under TEM.There may be either precusors of secretion or secre-tory granules in the plasma,and either desmosomes or poorly developedintercellular junctions.Bundles of intracytoplasmic tonofilaments werealso found in some cells.These results suggest that intermediate cellsare a kind of low-differentiated tumor cells with a potential to diffe-rentiate towards both prickle cells and acinar cells.In 4 cases transfor-mational changes of epithelium from normal appearance to hyperplasia, dysplasia and even carcinoma can be found in the larger duct.And inanother case,there are dysplastic lesions around the cancerous masses.The histological type of 3 cases in these 5 cases is solid epithelia masspredominance and the other 2 cases' type is mixed mucous gland withsolid epithelial mass.