乳腺叶状囊肉瘤是一少见的乳腺肿瘤，约占女性乳腺肿瘤的０．３％－０．９％。其组织结构与乳腺纤维腺瘤相似，含有上皮及间质两种肿瘤成份，叶状囊肉瘤间质细胞成份形态上有恶性特征。我科从１９８０年以来有５例，结合文献就其组织学特征，预后和治疗方法报道如下。ＩＩ... Breast cystosarcoma is a rare breast tumor, accounting for about 0.3%-0.9% of female breast tumors. The histological structure is similar to that of breast fibroadenoma. It contains both epithelial and mesenchymal tumor components. The stromal cell composition of cystosarcoma has a malignant appearance. Our department has had 5 cases since 1980. The combined histological features, prognosis and treatment methods are reported below. II...