Epithelial membrane antigen and DOG1 expression in minor salivary gland tumours.

Epithelial membrane antigen (EMA) and DOG1 are used as marker of epithelial cells, particularly the luminal cells, of salivary gland tumours. The aim of this study was to compare the EMA and DOG1 expression in tumours of minor salivary glands. Cases of pleomorphic adenoma (PA), basal cell adenoma (BCA), canalicular adenoma (CA), adenoid cystic carcinoma (ACC), polymorphous adenocarcinoma (PAC), mucoepidermoid carcinoma (MEC) and epithelial-myoepithelial carcinoma (EMC) were submitted to immunohistochemistry for EMA and DOG1. In PA and BCA, EMA and DOG1 were observed in luminal cells, while in CA the tumour cells were negative for both proteins. The EMA and DOG1 pattern expression detected in EMC was similar to that one observed in benign tumours. In ACC, both myoepithelial e epithelial expressed EMA and DOG-1. PAC tumour cells were only positive for DOG1, whereas MEC were only positive for EMA. In conclusion, EMA and DOG1 expression in benign salivary gland tumours was similar to normal salivary gland tissue and can be used as good marker of tumoral cells derived from intercalated ducts or its progenitor cells, while in malignant salivary gland tumours EMA expression is, however, better used as an indicator of aggressive behavior than a marker of luminal cells.

Canalicular adenoma--search for the cell of origin: ultrastructural and immunohistochemical analysis of 7 cases and review of the literature.

Canalicular adenoma (CA) is a rare, benign epithelial neoplasm of the salivary glands. Historically considered to be a variant of basal cell adenoma, this "monomorphic" adenoma has a distinct clinical, morphologic, and immunohistochemical profile. The putative cell of origin remains a topic of debate. A combination of morphology, immunohistochemistry, and ultrastructural analyses have been employed to determine histogenesis, but the interpretations of these studies have implicated multiple different cell types along the salivary gland duct as the cell of origin. The authors sought to further characterize CA using electron microscopy, immunohistochemistry, and special and immuno-stains on 7 cases. Their morphologic, immunohistochemical, and ultrastructural findings support a cell of origin demonstrating features of both the intercalated duct cells and the striated duct luminal epithelial cells.

Primary ductal adenocarcinoma of the lacrimal gland, associated with abundant intracytoplasmic lumens containing some eosinophilic hyaline globules: cytological, histological and ultrastructural findings.

A primary ductal adenocarcinoma (PDA) of the lacrimal gland is a rare distinct subtype of an epithelial tumor arising in the lacrimal gland. PDA is the counterpart of salivary duct carcinoma (SDC) resembling an invasive ductal carcinoma (IDC) of the breast. In our case, PDA revealed histopathological and immunohistochemical results corresponding to SDC. Interestingly, the tumor cells showed intracytoplasmic vacuoles containing dense eosinophilic hyaline globules at light microscopy. Ultrastructurally, the tumor cells exhibited microvilli-lined intracytoplasmic lumen containing homogenous electron-dense secretory products. A previous study demonstrated that numerous intracytoplasmic lumens of tumor cells are favored breast malignant tumor, similar to the histopathology of PDA, rather than benign lesion. This characteristic finding may be meaningful to diagnose high grade epithelial tumors including PDA.

A perspective of comparative salivary and breast pathology. Part I: microstructural aspects, adaptations and cellular events.

This is the first part of a review comparing the pathology of salivary and mammary glands. Here, less obvious similarities and differences in functional histology and their influences on pathology are examined with emphasis on myoepithelial cells, stromal components, analogues of mucosa-associated lymphoid tissue, steroid receptors, and intraparenchymal cells of monocytic lineage. Particular cell phenotypes (oncocytic, apocrine, neuroendocrine and clear) are critically evaluated and responses to atrophy, infarction and fine-needle aspiration biopsy procedures are highlighted together with aspects of metaplasia, regeneration, ageing and microcalcification. Areas of controversy or uncertainty which may benefit from further investigations are also discussed.

Preoperative assessment of salivary gland neoplasms with fine needle aspiration cytology and echography: a retrospective analysis of 357 cases.

Fine-needle aspiration cytology (FNAC) is a minimally invasive procedure usually well tolerated, easy to perform, quick, cheap and easy to repeat in case of doubts or non-diagnostic results. Echography is also a fast, cheap and non-invasive tool; however, the role of FNAC and echography in the diagnosis of salivary gland pathology is not universally recognised. Three hundred and fifty-seven patients with a cytological diagnosis at FNAC, and 247 of these who were also studied with echography, were enrolled for this retrospective study. The final histopathological diagnoses, obtained after surgery, were then compared to the preoperative FNAC diagnoses and echographic findings. From the analysis of our data, the overall FNAC specificity resulted 93 percent, sensitivity 83 percent, and diagnostic accuracy 92 percent. Echography sensibility was 57.1 percent specificity 98.2 percent, while positive and negative predictive value were respectively 80 percent and 94.8 percent. While echography can be useful in order to provide a better characterization of salivary gland lesions, FNAC can then be considered a safe diagnostic tool with reliable sensitivity and specificity for the assessment of salivary gland pathology and thus for selecting patients and indicating the best surgical treatment.

Collagenous crystalloids in myoepithelial carcinoma: report of a case and review of the literature.

Since the first report of "tyrosine crystals" in a parotid mixed tumor by Bullock in 1953, authors have described several types of crystalloids in association with mixed tumor and related neoplastic and nonneoplastic entities. The principal classes of these include tyrosine-rich crystalloids, collagenous crystalloids, and one class variously referred to as tyrosine-rich crystals, nontyrosine crystalloids, and amylase crystalloids. We report a myoepithelial carcinoma of minor salivary gland origin containing numerous collagenous crystalloids. To our knowledge, this represents the first report of collagenous crystalloids in a case of myoepithelial carcinoma. In addition, we searched our institution's files for cases of pure myoepithelial tumors. No crystalloids of any form were identified in 27 myoepitheliomas and 15 myoepithelial carcinomas. We review the literature on salivary-related crystalloids, and we propose the term oncocyte/cyst-associated crystalloids to encompass the aforementioned third class of crystalloid. Given distinct morphologic and histochemical properties and given relatively limited disease associations, we conclude that in the appropriate clinical context, the identification of these crystalloids can be diagnostically useful.

[Adenoid cystic carcinoma cells produce exosomes that promote tumor cell proliferation].

OBJECTIVE: To observe the effect of exosomes released by adenoid cystic carcinoma (ACC) cell line SACC-83 on the proliferation of ACC cells. METHODS: Exosomes were isolated from SACC-83 cell culture supernatants using total exosome isolation reagents. The whole-mount exosomes were characterized using transmission electron microscope and Western blotting. The exosomes were labeled with green fluorescent dye PKH67 and co-cultured with SACC-83 cells for 48 h, followed by staining with Alexa Fluor 594 phalloidin and DAPI to observe exosome uptake by the cells using laser scanning confocal microscopy (LSCM). The cell proliferation was assessed using MTT assay and wound healing assay, and the expressions of ERK and P-ERK in the co-cultured SACC-83 cells were detected using Western blotting. RESULTS: The exosomes isolated from SACC-83 cells showed a size range of 30-100 nm and expressed the exosomal markers CD9, CD63 and TSG101. LSCM showed exosome uptake by SACC-83 cells, which exhibited accelerated proliferation and significantly enhanced P-ERK expression (P < 0.05) without significant changes in ERK expression. CONCLUSIONS: SACC-83 cells produce exosomes that promote the tumor cell proliferation and enhances the cellular expression of P-ERK, suggesting a potential role of MAPK/ERK pathway activation in exosome-mediated acceleration of ACC cell proliferation.

Fine needle aspiration cytology of basal cell adenoma of the salivary gland.

OBJECTIVE: To formulate cytologic features for differential diagnosis of basal cell adenoma (BCA). STUDY DESIGN: The usefulness of 5 items for a cytologically definitive diagnosis of BCA was examined. The 5 items in 8 BCA and 22 non-BCA cases (adenoid cystic carcinoma [ADCC], basal cell adenocarcinoma, myoepithelioma, pleomorphic adenoma and polymorphous low-grade adenocarcinoma) that displayed mimicking cytology were examined cytologically. RESULTS: The useful items were < 5.1 microm in mean of epithelial nuclear short diameter; mild atypia on definitive diagnosis; stromal cell cluster combining smooth margin surrounding the epithelial cell cluster or containing the epithelial cell cluster; epithelial clusters surrounded by or adhered to a thick, hyalinized smooth margin without stromal cluster; and closely fastened, tight clusters with denser cytoplasm than ADCC, but an indistinct border, with oval nuclei and no hyaline cells. CONCLUSION: Five items are useful criteria for BCA.

Ultrastructural Characterization of Mammary Analogue Secretory Carcinoma of the Salivary Glands: A Distinct Entity from Acinic Cell Carcinoma?

Mammary analogue secretory carcinoma (MASC) of the salivary glands is a recently described neoplasm of the salivary glands with a characteristic morphology complemented by a specific cytogenetic translocation and gene rearrangements. Although immunophenotypic and cytogenetic differences allow for a more reliable distinction, ultrastructural features can also provide important information about the relationship between MASC, classic acinic cell carcinoma (AciCC), and AciCC intercalated duct cell-predominant variant. Following approval from the hospital's institutional review board, 7 cases of MASC, 8 cases of classic AciCC, and 4 cases of AciCC intercalated duct cell-predominant variant were retrieved from the pathology files of Massachusetts General Hospital from 2012 to 2015. Electron microscopy was performed using formalin-fixed, paraffin-embedded tissue. Ultrastructural features of all 19 neoplasms of the salivary glands were recorded. The predominant cell-types observed in MASC are those with intercalated/striated duct cell differentiation. These features include prominent invaginations of the cell surface studded with microvilli, and some intra- and intercellular lumina also with a microvillous surface. Classic AciCC dominant cell-type recapitulates acinar cell differentiation. These cells contain large intracytoplasmic zymogen-like granules. AciCC intercalated duct cell-predominant variant showed both cell populations in various proportions with the intercalated/striated duct cell type usually being the dominant one. MASC presents with distinctive ultrastructural features that allows its proper differentiation from classic AciCC. However, significant ultrastructural features overlaps between both AciCC intercalated duct cells-predominant and classic AciCC and MASC. These findings indicate a very close proximity between these tumors.

Mucoepidermoid carcinoma of the posterior-lateral border of tongue: a rare presentation.

Mucoepidermoid carcinoma (MEC) is the most common malignant tumour of the major and minor salivary glands. Minor salivary glands are scattered in different areas of the oral cavity such as palate, retromolar area, floor of the mouth, buccal mucosa, lips and tongue, but so far, only a few lingual MEC cases have been documented in the literature and most of the studies have shown a predilection for base and dorsum of the tongue. We report a rare case of MEC involving the posterior-lateral border of the tongue.

Combined DOG1 and Mammaglobin Immunohistochemistry Is Comparable to ETV6-breakapart Analysis for Differentiating Between Papillary Cystic Variants of Acinic Cell Carcinoma and Mammary Analogue Secretory Carcinoma.

BACKGROUND: We investigated the reliability of combined DOG1 and mammaglobin immunohistochemistry compared with ETV6 fluorescence in situ hybridization (FISH) in the assessment of salivary tumors previously diagnosed as acinic cell carcinoma (ACC). Ultrastructural features of cases reclassified as mammary analogue secretory carcinoma (MASC) were assessed by transmission electron microscopy (TEM). METHODS: Immunohistochemical (IHC) reactivity to DOG1 and mammaglobin was validated against FISH targeting the ETV6 gene in all 14 cases. RESULTS: Three cases with papillary cystic histomorphology previously diagnosed as ACC were revised to MASC. TEM features of the ETV6 rearrangement-positive MASC cases showed large numbers of secretory granules with extrusion into the intercellular spaces, well-developed endoplasmic reticulum, lipid-laden vacuoles, well-formed microvilli, and large lining cystic spaces. CONCLUSIONS: Combined DOG1 and mammaglobin immunohistochemistry is comparable to ETV6 -breakapart analysis for differentiating between papillary cystic variants of ACC and MASC.

Distinguishing adenoid cystic carcinoma from cylindromatous adenomas in salivary fine-needle aspirates: the cytologic clues and their ultrastructural basis.

The utilization of fine-needle aspiration (FNA) biopsy in salivary tumors is hindered by the reluctance of many cytopathologists to report adenoid cystic carcinoma (ACC) because its cylindromatous stroma is observed occasionally in pleomorphic adenoma (PA) and basal cell adenoma (BA), and a diagnosis of ACC results in radical surgery. The aim of this study is to identify dependable features to distinguish the look-alike entities and illustrate their ultrastructural base. We compared 20 cases of ACC to 15 cases of cylindromatous PA and 9 cases of BA. All were direct smears stained with Diff-Quik, hematoxylin and eosin, Papanicolaou, or Ultrafast Papanicolaou (UFP) stain. In addition to the presence of cylindromatous pattern, the amount of cytoplasm in the neoplastic cells and nuclear features were compared. Tissue was dissected from paraffin blocks and processed for electron microscopy in selected cases. The difference in nuclear features can be distinguished in UFP-stained smears and electron microscopy. The nuclei of ACCs were heterochromatic with coarse chromatin and irregular nucleoli, whereas the nuclei of PAs were euchromatic with fine chromatin and small compact nucleoli. The nuclei of BAs were hyperchromatic but finely textured. The cytoplasm of PAs was detectable with every stain at 40x objective, but the cytoplasm of BAs required UFP stain and 100x objective to be detected. The cytoplasm of majority of neoplastic cells of ACCs are invisible, because the thin rim of cytoplasm measured <1 microm ultrastructurally, well beyond the resolution of a light microscope. Rare cohesive fragment of epithelial cells in ACC have scanty blue cytoplasm in UFP stain and can be recognized as ductal cells. In conclusion, in our analysis of salivary tumors with a cylindromatous pattern, the seemingly naked nuclei of neoplastic cells with their coarse nuclear chromatin and irregular nucleoli, as revealed by the UFP stain, reliably distinguished ACC from cylindromatous adenomas.

Chromosome changes associated with the progression of cell lines from preneoplastic to tumorigenic phenotype during transformation of mouse salivary gland epithelium in vitro.

Two mouse salivary gland epithelial cell lines, CSG 211 and CSG 205/2B1, isolated during carcinogen-induced neoplastic transformation in vitro, were analyzed cytogenetically before and after they acquired the ability to produce carcinomas in syngeneic animals. With the use of Giemsa banding techniques, chromosome changes were identified that were associated with the transition from a preneoplastic to a fully transformed (tumorigenic) phenotype during serial passage in vitro. Results were compared with those from a third cell line of similar origin, CSG 225, which was tumorigenic at the earliest passage tested. These cell lines were found to be subtetraploid, which confirms previous data, and the tumorigenic lines showed consistent losses of copies of chromosomes 1, 4, 7, 9, and 14. Compared with their preneoplastic counterparts, the loss of no single chromosome seems to be sufficient to generate the tumorigenic phenotype, but the loss of a combination of some or all of these chromosomes appears to be important in the phenotypic transition. In CSG 211 the loss of chromosome 7 is probably more important in this respect than loss of the other chromosomes listed. The karyotype of this cell line undergoes major structural rearrangement, which suggests that loss of specific regions of chromosomes 1 and 9 is also important.

Transplantable murine salivary gland carcinoma (myoepithelioma). I. Biologic behavior and ultrastructural features.

Three salivary gland adenocarcinomas that arose spontaneously in female BALB/c mice, originally being maintained for plasmacytoma (MOPC) investigations, were studied; only one of the original hosts was MOPC-bearing. The initial carcinomas clearly originated from the salivary gland, not the breast, and did not resemble plasma cell lesions. The submandibular gland was the site of origin in each instance. Lesions were identical to those described previously in strains A and C mice as myoepitheliomas, with intracellular fibrils positive by phosphotungstic acid-hematoxylin (PTAH) stain. Each cell line (A, B, and C) of the salivary gland carcinomas was serially transplanted for 28, 29 and 14 generations, respecitvely. The lesion was easily transplanted, achieved almost 100% takes, and uniformly killed the host in 6-12 weeks, with metastasis to the peritoneum and liver. A myeloproliferative reaction characterized by leukemoid changes regularly occurred during the growth of the tumors. Each transplant generation was identical to its original salivary gland precursor by light and electron microscopy. In their growth pattern, the tumors resembled sarcomas with large areas of spindle cells. Ultrastructurally, the neoplastic cells contained the organelles of acinar and possibly ductal cells and exhibited varying degrees of synthetic and secretory activity, characterized by abundant free ribosomes and granular ergastoplasm, with prominent canaliculi containing abundant secretory material. Numerous desmosomes were seen, as well as coarse filaments and fine fibrils in most tumors cells, particularly in cells exhibiting lesser degrees of secretion. The filaments most likely represented the PTAH-positive intracellular fibrils observed by light microscopy. All tumors had numerous cells with resting features.

5-Azacytidine induction of stable myoepithelial and acinar cells from a human salivary intercalated duct cell clone.

A neoplastic human salivary intercalated duct cell clone was cultured in 5 microM 5-azacytidine for 5 days at 37 degrees C; then the cells were trypsinized and subcultured in growth medium without 5-azacytidine. Thereafter, subclones were cloned from the subculture. Of 12 subclones isolated, 7 clonal cell lines were established and characterized. The two subclones composed of cells which were spindle shaped or stellate exhibited phenotypes similar to those of myoepithelial cells such as microfibrils and myosin and formed a myoepithelioma upon transplantation of the cells into nude mice. The other five subclones were composed of polygonal cells with numerous secretory granules in their cytoplasm and containing amylase that seems to be specific to acinar cells; transplantation of these cells into nude mice resulted in production of acinic cell carcinoma. These findings indicate that a neoplastic human salivary intercalated duct cell is capable of at least bidirectional differentiation.

Biological characterization of pseudocyst-forming cell lines from human adenoid cystic carcinomas of minor salivary gland origin.

Two cell lines (ACCS and ACCY) were isolated from two individuals with adenoid cystic carcinoma (AdCC) using tissue culture techniques. Both cell lines have similar morphology, i.e., elongated and flattened cells with slender cytoplasmic processes. The two cell lines tend to form pseudocysts, which are a specific architectural feature of AdCC. Coexpression of cytokeratin and vimentin was found in the two cell lines, which occasionally also contained S-100 protein and lactoferrin or lysozyme immunoreactivity. Moreover, ACCS and ACCY displayed potential for the production of a large amount of extracellular matrix including basal lamina components such as fibronectin, laminin, and type IV collagen and glycosaminoglycans which are also part of the basal lamina. These findings suggest that the tumor cells, probably basal or myoepithelial like cells, are responsible for the formation of the peculiar stroma of AdCC consisting of a large amount of collagen-like fibers, basal lamina components, and mucopolysaccharides.

Intermediate-sized filaments and specific markers in a human salivary gland adenocarcinoma cell line and its nude mouse tumors.

The adenocarcinoma cell line HSG from human salivary gland, which proliferates in vitro or in nude mice, was examined by the immunoperoxidase method for the expression of three different types of intermediate-sized filaments (IFs) and of specific antigens such as carcinoembryonic antigen, S-100 protein, secretory component, lactoferrin, myosin, tropomyosin, and actin. The cultured HSG cells were found to express three different types of IFs defined by antibodies to keratin, vimentin, and desmin. In HSG cells proliferating in vitro at 34 degrees C and 37 degrees C but not at 39 degrees C, the expression of tropomyosin and carcinoembryonic antigen was observed, although myosin and S-100 protein were not detected. The expressions of actin, lactoferrin, and secretory component were restricted to cultured HSG cells at 39 degrees C and 37 degrees C, respectively. Transplantation of HSG cells into nude mice resulted in the establishment of a nude mouse system with malignant characteristics such as invasion and metastasis. The expression of IFs in the primary tumors was restricted to keratin and desmin IFs, whereas coexpression of keratin, vimentin, and desmin IFs was observed in some neoplastic cells present in the metastatic tumors in regional lymph nodes and lung. In addition, expression of actin, myosin, tropomyosin, and S-100 protein was found in the metastatic tumors, whereas myosin and S-100 protein were not detected in the primary tumors. Moreover, the metastatic tumors were almost occupied by the neoplastic cells with oncocytic changes, although oncocytic change was not found in the cultured HSG cells and their primary tumors.

Expression of neurofilaments in a neoplastic human salivary intercalated duct cell line or its derivatives and effect of nerve growth factor on the cellular proliferation and phenotype.

A neoplastic salivary cell line with an ultrastructure similar to that of an intercalated duct cell of the salivary gland, established from a human submandibular salivary gland, has been used in our laboratory as a model for studying mechanisms regulating cytodifferentiation in salivary glands. The expression of neurofilaments (Mr 200,000, 160,000, and 68,000) in the neoplastic human salivary intercalated duct cell line and its derivatives was found by the immunofluorescence staining technique, immunoblotting, or immunoelectron microscopy. In addition, these cells stained with Bodian impregnation and expressed specific antigens such as tubulin alpha and beta chain, HNK-1 antigen, and laminin. When these cells were cultured in the presence of nerve growth factor, only the cells with a myoepithelial cell phenotype formed the long cytoplasmic processes which were densely packed with ample microfibrils in addition to microtubule bundles, and they exhibited marked suppression of anchorage-independent and anchorage-dependent growths. These findings indicate that the characteristics of neoplastic human salivary intercalated duct cell line and its derivatives are similar to those of neuronal cells.

Myoepithelial carcinoma of the lung arising from bronchial submucosa.

Myoepithelial neoplasm mainly occurs in the salivary glands and breasts and is extremely rare in the lung. To our knowledge, this report describes the first documented case of a myoepithelial carcinoma present in the lung. The tumor derived from the right main bronchial submucosa and exhibited a dual epithelial and smooth muscular phenotype by immunohistochemical and ultrastructural studies. It invaded the neighboring pulmonary tissue and the hilar lymph nodes. Despite a right pneumonectomy and chemotherapy, metastasis was found in the left lung 7 months later.

Plasmacytoid monomorphic adenoma of salivary glands. Absence of myogenous differentiation and comparison to spindle cell myoepithelioma.

The immunohistochemical and ultrastructural features of two salivary gland monomorphic adenomas composed of plasmacytoid cells (so-called plasmacytoid myoepitheliomas) were studied to determine if the plasmacytoid cells contained detectable evidence of myogenous differentiation. The results were compared with the immunohistochemical profile of three salivary gland myoepitheliomas of spindle-cell type. The plasmacytoid tumors were each immunoreactive for vimentin, cytokeratin, S100 protein, and glial fibrillary acidic protein (GFAP). They were negative for muscle-specific actin (MSA), smooth-muscle actin (SMA), and desmin. Conversely, two of three spindle-cell myoepitheliomas were immunoreactive for MSA and SMA, in addition to vimentin, cytokeratin, and S100 protein. One tumor also contained focal positivity for desmin and GFAP, and a single spindle-cell tumor was vimentin-positive only. Ultrastructurally, plasmacytoid cells were characterized by focal desmosomes, basal lamina, and abundant intermediate cytoplasmic filaments. Dense bodies typical of smooth-muscle cells and actin-sized filaments were absent. Immunohistochemically and ultra-structurally, the plasmacytoid cells lack any evidence of myogenous differentiation and should not be considered a subtype of myoepithelioma.