Sow-Yeh Chen

Odontogenic myxoma. A clinical and ultrastructural study.

The odontogenic myxoma is an uncommon neoplasm of the jaws that is believed to arise from the primitive, mesenchymal portion of the tooth germ. This study surveys nine cases of odontogenic myxoma of the jaws. Analysis of the clinical material revealed that the myxoma occurred most frequently in the posterior regions of the mandible and will recur if initial therapy is too conservative. The average age of the patients in this series was 26.5 years. Five cases involved females and four involved males. Electron microscope findings revealed that the tumor cells are probably responsible for the secretion of the myxomatous intercellular material of the neoplasm.

Central granular-cell tumor of the jaws (the so-called granular-cell ameloblastic fibroma)

Four cases of central granular-cell tumor of the jaws were evaluated to determine the clinical parameters of the lesion, and one of these cases was examined with the electron microscope to investigate the nature of the granular cells. The average age of the patients at the time of treatment was 55 years; all four patients were women. Three of the lesions originated in the mandible, and one in the maxilla. Follow-up studies revealed no recurrences. Electron microscopic examination of one case revealed that the granular cells contained many lysosome-like particles and that these cells are identical to those found in the granular-cell myoblastoma.

Acinic cell adenocarcinoma of minor salivary glands.

Nineteen cases identified as acinic cell adenocarcinoma of minor salivary glands from the files of the Armed Forces Institute of Pathology and the Department of Pathology, Temple University School of Dentistry were studied to determine the clinical and histomorphologic parameters of this lesion. One case was examined ultrastructurally. Clinical results show that the tumor is more common in females and the average age of all patients was 42.5 years. The most common sites were upper and lower lips and buccal mucosa. The tumor tends to be locally limited, but recurrence is a distinct possibility. Cytologic features usually associated with malignancies are generally not present. However, perineural space and muscle invasion occur, and it is felt that this tumor should be considered as a low‐grade malignancy. Fine structural observations showed the presence of cells with serous secretory granules and cells with mucous globules. However, the serous secretory granules were not as numerous as those reported in the acinic cell adenocarcinoma of the parotid gland. It appears that these tumors arise from intercalated duct cells or pluripotential duct cells rather from fully differentiated serous cells.

Oral granular-cell tumors: Report of twenty-five cases with electron microscopy

Twenty-five cases of granular-cell tumor of the oral cavity are reported. The clinical findings are similar to previously published data. Of five cases studied by electron microscopy, three were processed directly from fresh surgical specimens and two cases were processed following initial formalin fixation. The granules for the most part are morphologically compatible with lysosomes except for a single variety containing viruslike particles. There is increasing evidence in support of a neural origin, but the indications are that more than one cell type may be the progenitor of granular cells of the granular cell tumor.

Neurofibroma and schwannoma of the oral cavity: A clinical and ultrastructural study

The clinical parameters of fifty-five cases accessioned as neurofibroma and schwannoma of the oral cavity were reviewed. An electron microscope study was performed on several cases. The component cells of neurofibroma were spindle shaped, with bundles of collagen fibrils between cells. Junctional complexes were observed between adjacent cells. Component cells of the schwannoma showed numerous convoluted cytoplasmic processes. Reduplication of basal lamina was frequently observed and formed the material in the hyalinized area of Verocay bodies.

Ultrastructure of oral squamous-cell carcinoma.

Fresh surgical specimens of sixteen cases of oral squamous-cell carcinoma were processed for electron microscopic study. All cases were histologically graded as moderately differentiated carcinoma. As compared to normal oral stratified squamous epithelium, some unusual ultrastructural features were present in carcinoma. These features were spherical or ovoid nuclear bodies composed of concentrically arranged filaments and granules, clustered ribosomes, many lysosomal bodies, cell residues in other cells, absence and multilayering of basal lamina, pseudopodal cytoplasmic projections, microfilaments in peripheral cytoplasm, clusters of swirled tonofilaments, intracytoplasmic desmosomes, and a small amount of glycogen. These features are interpreted as being related to hyperactivity, phagocytosis, locomotion, and differentiation of cancer cells.

Adenoid cystic carcinoma of minor salivary gland

Abstract Five cases of adenoid cystic carcinoma of minor salivary glands were studied. The mucoid material in the characteristic cystlike spaces of this neoplasm was diastase-resistant periodic acid-Schiff (PAS)—positive, alcian blue-positive, toluidine blue-positive, and mucicarmine-positive. Verhoeff-Van Giesons method and Weigerts method did not reveal elastic tissue in the cystlike spaces. Mallorys method revealed that a central core in cystlike spaces was similar in stainability to collagen. Wilders method did not reveal reticular fibers in these spaces. Electron microscopy revealed three readily recognizable zones: a juxtacellular zone of a network of replicated basal lamina, an intermediate zone of stellate granules of mucoid material, and a central core of densely packed aperiodic filaments or collagen fibrils. The histogenesis of cystlike spaces and their relationship with biologic behaviors of the neoplasm were discussed.

Estrogen receptor assay in polymorphous low-grade adenocarcinoma and adenoid cystic carcinoma of salivary gland origin. An immunohistochemical study.

An apparent relationship between breast cancer and salivary gland cancer has been observed, and there is one report in the literature that describes estrogen receptors in normal salivary gland and salivary gland cancers. With the use of a monoclonal antibody against estrogen receptor protein and the avidin-biotin immunoperoxidase procedure, we were unable to demonstrate estrogen receptors in formalin-fixed paraffin-embedded sections of either polymorphous low-grade adenocarcinoma or adenoid cystic carcinoma of salivary gland origin.

Canalicular adenoma of the upper lip. An electron microscopic study

Canalicular adenoma is composed of a row of tall columnar cells adjacent to canalicular lumina and a row of conical cells adjacent to connective tissue stroma. It differs from basal cell adenoma, of the parotid by the lack of well developed desmosomes associated with bundles of tonofilaments; by the presence of moderate numbers of cell organelles; by a single, inconspicuous basal lamina instead of multi‐layering; and by the presence of mucoid material in the stroma. Results suggest that this type of tumor should be considered a specific benign entity of the salivary glands. Cytologic features also suggest that it originates in excretory duct cells of minor salivary glands. Cancer 46:552–556, 1980.

Ultrastructure of mucoepidermoid carcinoma in minor salivary glands

Three cases of mucoepidermoid carcinoma of minor salivary glands were studied by electron microscopy. Mucus-secreting cells contained numerous mucous globules and bundles of fine cytoplasmic filaments. Another cell type contained a large number of glycogen particles, akin to tumor cells in glycogen-rich adenocarcinoma, and it is postulated that these cells represent the intermediate cells observed by light microscopy. Epidermoid cells contained a moderate amount of tonofilaments and various numbers of organelles. Mucus-secreting and epidermoid cells that surrounded a cystic space exhibited many microvilli. Results of this study support the theory that mucoepidermoid carcinoma develops from salivary gland duct cells with different cellular differentiation potentials and, in general, agree with the conventional grading system of mucoepidermoid carcinoma.