[Clinicopathologic and immunohistochemical study on 8 cases of malignant mixed müllerian tumor].

The clinico-pathological features of eight cases of malignant mixed müllerian tumor, a rare neoplasm composed of an admixture of epithelial and stromal elements, are reported. Four of the tumors located in the endometrium, three in the cervix and one in the ovary. Microscopically, the epithelial elements ranged from poorly to well differentiated adenocarcinoma. Homologous stromal sarcoma cells were present in six tumors and heterologous elements were also seen in the other two tumors. Immunohistochemical studies showed diffuse cytoplasmic staining of keratin in the epithelial elements of all the eight cases. Sarcomatous cells were positive focally for keratin in four spindle cell sarcoma cases. Desmin immunoreaction was moderately positive in the sarcomatous element of four neoplasms. Follow-up result was available in 7 patients of whom 3 survived and 4 died from recurrence or metastasis. Immunohistochemical findings support the stem cell origin of this tumor.