本文报道3例黑色素性髓母细胞瘤的临床、光镜及电镜观察。结果发现:光镜下,主要由小型的肿瘤细胞及灶性的黑色素细胞构成;电镜下,小型肿瘤细胞绝大部分为未分化的细胞。黑色素细胞浆内含有许多黑色素小体,胞体周围部分或全部被基底膜样物质包绕。作者推测黑色素细胞可能系神经嵴起源,而小型瘤细胞可能系神经上皮起源。 This article reported three cases of melanotic medulloblastoma clinical, light and electron microscopy observations. The results showed that: under light microscope, mainly composed of small tumor cells and focal melanocytes; under electron microscope, the majority of small tumor cells are undifferentiated cells. The melanocyte cytoplasm contains many melanosomes, and part or all of the cell body is surrounded by basement membrane-like material. The authors speculate that melanocytes may be the source of neural crest, while small tumor cells may be of neuroepithelial origin.