Hyaline globule-like structures in undifferentiated sarcoma cells of malignant müllerian mixed tumor of the fallopian tube.

Malignant müllerian mixed tumors (MMMTs) of the fallopian tube are very rare neoplasms, and we present such a case with unusual findings here. A 57-year-old Japanese woman, after she received a medical checkup, underwent salpingo-oophorectomy on the suspicion of ovarian cancer. At the time of operation, the main tumor was present predominantly in the fallopian tube. Microscopically, the tumor consisted of carcinoma and sarcoma components. The carcinoma showed moderately to poorly differentiated adenocarcinoma. The sarcoma consisted of predominantly undifferentiated sarcoma and focally rhabdomyosarcomatous cells with abundant eosinophilic cytoplasm. Immunohistochemically, the differentiation toward rhabdomyosarcoma was confirmed. Interestingly, the cytoplasm of undifferentiated sarcoma cells contained hyaline globule-like structures. These structures showed a positive reaction for PAS, and these structures were not digested by the diastase pretreatment. Ultrastructurally, hyaline globule-like structures corresponded to lysosomes. Finally, pathologists should keep in mind that undifferentiated sarcoma cells in MMMT of the fallopian tube may contain hyaline globule-like structures in the cytoplasm.

Uterine malignant mixed Müllerian tumor (Metaplasic carcinoma) in the cat: clinicopathologic features and proliferation indices.

A homologous malignant mixed Müllerian tumor of the uterus occurring in an 8-year-old Persian cat was described with regard to its clinical and pathologic features. A polypoid multinodular mass of the right uterine horn was shown by an ultrasound examination. Grossly, the right uterine horn was enlarged because of a vegetative and infiltrating tumor, grayish-white in color, that penetrated the uterine wall to the level of the perimetrium. Many metastatic nodules were found in abdominal and thoracic cavities. Histologically, the neoplasm had both carcinomatous and sarcomatous components and was diagnosed as an uterine malignant mixed Müllerian tumor. This is the fourth case reported in cats. The histologic features and proliferation rate of this tumor were similar to the corresponding human neoplasms, which occur mainly in postmenopausal women. The possible hormone dependence of the tumor is briefly discussed.

Three-dimensional culture of a mixed mullerian tumor of the ovary: expression of in vivo characteristics.

The Rotating-Wall Vessel (RWV) is a novel in vitro cell culture system used to successfully culture a cell line derived from a heterologous mixed mullerian tumor cell of the ovary. Although the original tumor was comprised of both epithelial and mesodermal components, long-term culture in conventional flasks established a cell line from this tumor with homogeneous epitheliallike growth characteristics (1). Cells from Passage 36 were seeded into a Rotating-Wall Vessel containing Cytodex-3 microcarrier beads. Scanning electron micrographs of tumor cells cultured for 32 d in the RWV showed the presence of heterogeneous cell populations organized into three-dimensional tissuelike architecture. Immunocytochemical analysis confirmed the cellular heterogeneity, as demonstrated by expression of both epithelial and mesenchymal antigens. Reverse transcription polymerase chain reaction amplification demonstrated the presence of mRNA for cellular oncogenes HER-2/neu, H-ras, K-ras, and tumor suppressor p53. Thus, there are two advantages to propagation of tissue in the RWV culture system:(a) tissue diversification representing populations present in the original tumor, and (b) the three-dimensional freedom to organize tissues morphologically akin to those observed in vivo. These data indicate that the RWV culture system is suitable for generating large quantities of ovarian tumor cells in vitro that are amenable to immunocytochemical, oncogenic, morphologic characteristics demonstrated in vivo.

Adenosarcoma of the uterus with extensive smooth muscle differentiation: ultrastructural study and review of the literature.

Four cases of Mullerian adenosarcoma were studied by light and electron microscopy and immunohistochemistry. All 4 cases showed the histologic characteristics of adenosarcoma with benign endometrial glands and a malignant stroma. Ultrastructurally, the epithelial component in all cases had the appearance of proliferative endometrial glands, and the malignant mesenchymal cells showed features of endometrial stroma. A distinct basal lamina separating glands from stroma was present. In addition, 2 of the cases showed extensive smooth muscle differentiation which was associated with sarcomatous overgrowth. The smooth muscle features were confirmed by immunohistochemistry. Multiple theories of the histogenesis of this tumor are discussed.