Malignant myoepithelioma of the larynx with massive metastatic spread to the liver: an ultrastructural and immunocytochemical study.
A malignant myoepithelioma arising in the submucosal glands of the larynx of a 71-year-old man is reported. The patient presented with a neck mass and massive metastatic involvement of the liver. Light microscopy of a liver biopsy specimen and fine-needle aspiration sample of the neck mass revealed a poorly differentiated carcinoma. Electron microscopic study of a second liver biopsy specimen demonstrated unequivocal features of myoepithelial differentiation; this was further confirmed by the strong cytokeratin and S-100 protein positivity and carcinoembryonic antigen negativity of the tumor cells. Myoepitheliomas are rare tumors, and most reported cases have been benign or of low-grade malignancy. The present case is unique because of its mode of presentation and fulminant course. It also underscores the usefulness of electron microscopy as a diagnostic modality in the work-up of metastatic lesions.
Ibrahim
R
R
Department of Laboratory Service, Harvard Medical School, Boston, Massachusetts.
Bird
D J
DJ
Sieler
M W
MW
D000368:Aged; D002272:Carcinoembryonic Antigen / Q000032:analysis; D002467:Cell Nucleus / Q000648:ultrastructure; D003593:Cytoplasm / Q000648:ultrastructure; D006801:Humans; D007633:Keratins / Q000032:analysis; D007822:Laryngeal Neoplasms / Q000737:chemistry / Q000648:ultrastructure*; D008113:Liver Neoplasms / Q000556:secondary* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D009208:Myoepithelioma / Q000737:chemistry / Q000648:ultrastructure*; D009418:S100 Proteins / Q000032:analysis; D014746:Vimentin / Q000032:analysis
D002272:Carcinoembryonic Antigen; D009418:S100 Proteins; D014746:Vimentin; D007633:Keratins