of the vulva: clinical outcome and pathology.
Immunolocalization of the smooth muscle-specific protein calponin in complex and mixed tumors
of the mammary gland of the dog: assessment of the morphogenetic role of the myoepithelium.
25) Thyroid transcription factor 1 reactivity was consistently negative in the non-small cell component of mixed tumors
and the tumors reclassified as non-SCC in our study and is therefore helpful along with the other stains in classification of the histologic subtype.
of salivary type can also be seen in the lung, but these would be expected to demonstrate, by morphology and immunohistochemical staining, patterns consistent with myoepithelial cells in at least part of the tumor.
, polymorphous low grade adenocarcinoma and adenoid cystic carcinoma of the salivary gland: pathogenic implication and differential diagnosis by Ki-67 (MIB 1), BLC 2 and S-100 immunohistochemistry.
21] In a clinicopathologic study of 146 cases of malignant mixed tumor
of the salivary gland, the authors described occasional examples of clearly malignant spindle cell or mixed spindle cell and giant cell variant tumors, some of which exhibited predominantly diffuse pseudosarcomatous pattern.
Spindle cell epitheliomas of the vagina (SCEVs) or "mixed tumors
of the vagina" have some important differences from mixed tumors
that arise in other areas, such as skin, salivary glands, breast, mediastinum, and trachea.
have also been seen, leading to the hypothesis that both types of tumor arise from a pluripotential epidermal stem cell damaged by ultraviolet light.
Less than 5% of all salivary gland tumors occur in children; these tumors are approximately 10 times more likely to take place in the parotid gland than in the submandibular gland, (1-9) Pleomorphic adenomas, also called mixed tumors
for their remarkable histologic diversity, represent about 60% of all tumors in the parotid gland; however, like all salivary gland tumors, they are far less common in the submandibular gland.
Rare mixed tumors
classified as hepatoblastomas with teratoid features show variable amounts of other heterologous elements such as stratified squamous, mucinous, and ductular cholangioblastic epithelium, immature neuroepithelium, neuroendocrine differentiation, and melanin pigment.
Neurofibromas are mixed tumors
made up of axons, Schwann cells, and fibroblasts coated in a collagen or mucoid matrix.
Benign mixed tumors
are neoplasms that exhibit features of both epithelial and mesenchymal origin.
The histologic differential diagnosis includes eccrine carcinoma, mucin-producing adenocarcinoma with squamous differentiation, primary cutaneous adenosquamous (mucoepidermoid) carcinoma, and malignant mixed tumors
of the skin.
Perhaps one of the most elegant studies supporting this hypothesis is from Thompson and colleagues, (17) who used carcinoma cells and sarcoma cells obtained from 6 malignant, mixed tumors
identified in 4 different organs and demonstrated clonal identity and monoclonality between the 2 cell types in all cases.
Clinically, mixed tumors
are confined to the middle ear and mastoid; they rarely involve the otic capsule or facial nerve, and they may be misdiagnosed as chronic otitis media.