心脏黏液瘤的临床病理学特征——47例分析

Clinicopathologic Features of Cardiac Myxoma-a Report of 47 Cases

背景与目的:心脏黏液瘤是心脏肿瘤中最常见的一种,形态结构多样,而生物学行为及组织发生尚存争议。本研究探讨心脏黏液瘤的临床特征、组织形态及免疫表型特点。方法:复习47例心脏黏液瘤临床资料及组织切片,对部分病例作特殊染色及10种抗体的免疫组化染色并观察其结果。结果:47例心脏黏液瘤中女性患者较多,占32例,年龄最小者3岁。肿瘤体积0.7cm×0.7cm×0.4cm～12cm×8cm×7cm,42例有蒂,5例无蒂;43例位于左心房,3例位于右心房,1例位左心室近心尖部。瘤细胞呈星芒状、梭形、圆形或不规则形,排列呈小团及索状,其间有大量黏液。4例可见瘤细胞围绕小血管排列,4例表面有一层增生纤维组织形成的假包膜,2例间质呈血管瘤样改变;7例间质有大片陈旧性出血、含铁血黄素及铁盐沉积、纤维化;1例有灶状腺样结构,1例有骨化及脂肪化生,1例富于细胞。12例作免疫组化,Vimentin及CD34肿瘤表面被覆细胞及实质内细胞为阳性;腺样分化区CK及EMA阳性;富于细胞的1例PCNA及Ki67阳性。随访21例,随访1～15年,未见复发。结论:心脏黏液瘤有腺样化生、陈旧性出血、纤维化、骨化及脂肪化生等多种继发性改变,富细胞者是否存在潜在恶性,尚待进一步研究。心脏黏液瘤可能起源于多潜能原始间叶细胞。

BACKGROUND ＆ OBJECTIVE. Myxoma is the most common neoplasm of the heart, and has various morphologic structures, but its biological behaviors and histogenesis are still controversial. This study was to summarize the clinical, histomorphologic, and immunophenotypic features of cardiac myxoma. METHODS; The clinical data and HE sections of 47 cases of cardiac myxoma were reviewed. Special staining and immunohistochemical staining for 10 kinds of antibodies were carried on some cases to observe the morphologic features. RESULTS, Of the 47 patients with cardiac myxoma, 32 were women, the youngest was 3 years old. The volume of tumors ranged from 0.7 cm×0.7 cm × 0.4 cm to 12 cm × 8 cm × 7 cm. Of the 47 tumors, 42 were pedunculated, the rest had broad fundus without pedicel; 43 located in the left atrium, 3 in the right atrium, and 1 in the left ventricle where near to the apex of heart. Tumor cells were stellate, spindle, round, or irregular, and arranged as masses or stripes, with abundant mucus around them. Tumor cells surrounded arterioles in 4 cases. Pseudo-capsule was formed by hyperplastic fibrous tissue in 4 cases. The mesenchyma presented angiomatous fashion in 2 cases. Sheets of old hemorrhage, hemosiderin and iron salt deposition, and fibrosis were observed in 7 cases. One case had foci adenoid structure, 1 lipoid metaplasia and ossification, 1 was rich of cells. Vimentin and CD34 were found in lining cells and parenchymal cells in 12 cases. Cytokine kinase （CK） and epithelial membrane antigen （EMA） were positive in the region of adenoid differentiation. Proliferating cell nuclear antigen （PCNA） and Ki67 were positive in the cell-rich tumor. None of the 21 patients had tumor recurred after follow-up. CONCLUSIONS. Cardiac myxoma has various secondary morphologic changes, including adenoid metaplasia, old hemorrhage, fibrosis, ossification, and lipoid metaplasia. Whether the cell-rich tumors tend to be malignant needs further study. Cardiac myxoma may come from multipotential mesenchymal cells.