Clear cell carcinoma of salivary glands: immunohistochemical evaluation of clear tumor cells.

A total of 14 cases of clear cell carcinoma of salivary glands were evaluated by immunohistochemical methods using monoclonal antibodies to cytokeratin (K1.1 and K8.12), vimentin, S-100 alpha and beta subunits, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), MAM-3 and MAM-6 antigens and proliferating cell nuclear antigen (PCNA), as well as polyclonal antibodies to lysozyme (Ly), lactoferrin (la) and Alpha-1-antichymotrypsin (alpha 1-Ach). Histopathologically, the carcinoma was characterized by round or polygonal tumor cells with cytoplasm that does not stain with hematoxylin and eosin, nuclei with little pleomorphism and few or no mitotic figures, and growing in solid sheets, small nests or cords with collagenous stroma. Cytokeratin KL1 and K8.12 was present in few tumor cells with almost negligible to strong reaction in all cases, vimentin in 6, GFAP in 5 cases with multiple-expression of cytokeratin K8.12, vimentin and GFAP in 5 cases. S-100 protein immunoreactivity was the most prominent feature with more intense reaction of S-100 beta than S-100 alpha subunit. NSE reactivity was seen in 6 cases. Ly, La, a1-ch, MAM-3 and MAM-6 antigens were localized in clear cells with various reaction intensities. The authors conclude that the clear tumor cells in clear cell carcinoma of salivary glands are not myoepithelial in origin but epithelial or neuroectodermal/neural crest in origin, showing ductal differentiation at the immunohistochemical level.

Myoepitheliomas and myoepithelial adenomas of salivary gland origin. Immunohistochemical evaluation of filament proteins, S-100 alpha and beta, glial fibrillary acidic proteins, neuron-specific enolase, and lactoferrin.

Immunohistochemical identification of keratin proteins (TK, KL1 and PKK1), vimentin, myosin, S-100 protein (using polyclonal antiserum) and S-100 alpha and beta subunits, glial fibrillary acidic protein (GFAP), neuron-specific enolase (NSE), lactoferrin, and lysozyme was made in myoepitheliomas, myoepithelial adenomas, and clear cell adenomas of salivary gland origin. Myoepithelioma cells were divided into two types: plasmacytoid cells, which showed great heterogeneity in terms of keratins and S-100 alpha and beta proteins and a lack of GFAP, NSE, lactoferrin, and lysozyme in most the cells, and fibrous and dendritic tumor cells, which displayed variable staining for keratin and S-100 alpha and beta proteins. Myoepithelial adenomas were composed of small-, intermediate-, and large-sized spindle cells that showed irregular positive reactions for keratins and S-100 alpha and beta. Immunohistochemical deposition of S-100 protein was restricted strongly to the dendritic cells present in hyalinous and myxomatous areas. Clear cell adenomas revealed uniformly slight staining of keratins and S-100 proteins, and negative staining or rarely positivity for GFAP, NSE, lactoferrin, and lysozyme. When the immunohistochemical deposition of these proteins was compared between normal glands and myoepithelial tumors, heterogeneity of expression of keratins, S-100 proteins, GFAP, and NSE was notable in the tumors. Progenitor cells of several kinds of myoepithelioma were suggested to be intercalated reserve cells, which are thought to be the same cell that gives rise to pleomorphic adenoma of salivary glands.

Immunohistochemical localization of the alpha and beta subunits of S-100 protein in pleomorphic adenoma of the salivary glands.

The immunohistochemical expression of the alpha and beta subunits of S-100 protein in reactive, modified and transformed of myoepithelial cells, salivary pleomorphic was investigated using monoclonal antibodies. With S-100 alpha, normal salivary glands showed strong staining in serous acinar cells and moderate to slight staining in ductal segments, and with S-100 beta staining was slight or negative in acinar cells, but strong in nerve fibres. In pleomorphic salivary adenomas, the immunohistochemical distribution of S-100 alpha and beta proteins indicated great variation in the tumour cells. Some neoplastic cells gave similar staining for both S-100 alpha and beta, others were strongly positive for S-100 alpha and stained only slightly for S-100 beta, or vice versa. Yet other cells were positive for S-100 alpha and negative for S-100 beta, or vice versa. Pleomorphic salivary adenomas were classified both by histopathological criteria and by their staining pattern for S-100 alpha and beta proteins. Great heterogeneity in S-100 alpha and beta protein expression was found in individual tumour cells of both ductal and myoepithelial origin, and no regular pattern was identified. The cellular origin of salivary pleomorphic adenomas is discussed in terms of S-100 alpha and beta protein immunohistochemistry. Pleomorphic adenoma cells may be transformed from reserve cells into tumour cells displaying biologic properties of myoepithelial cells, ductal cells, or a mixture of both.

Immunoreactive prolactin in lesions and tumours of salivary glands.

The prolactin binding in obstructive lesions and tumours of salivary glands was described by use of the immunohistochemical PAP technique. Normal salivary glands had prolactin binding cells in the striated ducts only. Chronic obstructive lesions of submandibular glands showed negative immunoreaction for prolactin binding in ductal cells, but positive staining of the luminal surface of ductal segments. In pleomorphic adenomas, occasional neoplastic cells located along the luminal borders of tubular, ductal, or of duct-like epithelial structures were strongly reactive with anti-prolactin and 26.5% of cases pleomorphic adenoma were positive for anti-prolactin. Adenoid cystic carcinoma exhibited positive prolactin binding on the luminal surface of some of tumour foci, but not in the rest of the tumour. Warthin's tumour was devoid of detectable prolactin binding.

Immunohistochemical localization by monoclonal antibody of human epidermal growth factor in mixed tumours of the skin.

Immunohistochemical distribution of human epidermal growth factor (hEGF) was described in 17 cases of mixed tumour of the skin with monoclonal antibody. In normal sweat glands, epithelial cells in the secretory portion and in the transitional area between secretory portion and duct showed prominent staining for hEGF. In the salivary pleomorphic adenoma type of mixed tumour of the skin, luminal tumour cells of tubular and duct-like structures gave a very characteristic hEGF staining reaction. The tumour cells showing strong staining for hEGF were scattered throughout the solid foci in this type of mixed tumour. Tubular epithelial cells in the clear cell adenoma type also displayed a positive hEGF reaction. And apocrine mixed tumours strong staining for hEGF occurred on the apical side of tubular and ductal tumour cells. In view of the immunohistochemical staining patterns for hEGF, the histologic origin of mixed tumours of the skin is suggested to be cells in the secretory portion and those in the transitional portion between secretory portion and duct of the sweat gland.

Various expressions of modified myoepithelial cells in salivary pleomorphic adenoma. Immunohistochemical studies.

Variant expressions of modified myoepithelial cells in salivary pleomorphic adenomas are described as determined by immunohistochemical techniques which visualized the distributions of S-100 protein, intermediate-sized filament proteins (keratin, vimentin, and desmin), and contractile proteins (myosin and actin), as well as lysozyme and lactoferrin. Immunohistochemical staining patterns of S-100 protein were basically used to classify modified myoepithelial cells, along with histologic criteria. Histochemical modifications of myoepithelial cells in pleomorphic adenoma of salivary glands could be divided into a) reactive, b) transformed, and c) neoplastic myoepithelial cells. Reactive myoepithelial cells were stromal-like cells which displayed an intense S-100 protein reaction. Transformed myoepithelial cells were negative or slightly positive for S-100 protein; they were located in the outer zone of tubular or duct-like structures and were spindle-shaped. The inner round cells of tubular and ductal structures, which could be ductal origin, gave intense keratin staining, as well as marked reactions for lysozyme and lactoferrin. Neoplastic myoepithelial cells were plasmatoid or fibrous types of cells and contained abundant S-100 protein and vimentin. These cells were termed "myoepithelioma" as in classical diagnosis.

Immunohistochemical distribution of human epidermal growth factor in salivary gland tumours.

Immunohistochemical identification of human epidermal growth factor (hEGF) was carried out in a total of 152 cases of salivary gland tumours, consisting 107 pleomorphic adenomas and their variants, 13 adenolymphomas and 32 adenoid cystic carcinomas. A high percentage of pleomorphic adenomas revealed markedly positive hEGF staining of the luminal surface cells of tubuloductal structures and of modified or neoplastic myoepithelial cells. Clear cells of the tumour showed various reactivities from very slight to strong. Eosinophilic epithelial cells of adenolymphoma gave a positive reaction for hEGF in all the cases, whereas most adenoid cystic adenoma lacked hEGF staining; however some cases showed positive staining of the tumour cells. The immunohistochemical detection of hEGF in most salivary gland tumours suggests this factor to be a possible new marker of salivary glands tumours, and to have a biological role in tumour proliferation.

Immunohistochemical detection of human epidermal growth factor in submandibular glands and their tumors using a polyclonal antiserum and a monoclonal antibody.

We applied immunohistochemical procedures to detect hEGF in salivary glands and pleomorphic adenomas of salivary-gland origin using a polyclonal hEGF antiserum and a monoclonal antibody against hEGF synthesized by applying the synthetic gene technique using Escherichia coli. In normal salivary glands, hEGF was mainly localized in the ductal system (i.e., intercalated, striated, and excretory ducts). The staining intensity and intracellular localization exhibited some variation depending on the fixative used. When a polyclonal hEGF antiserum was used for immunostaining, slight background staining was observed in sections prepared using the fixatives tested. Therefore, precise localization of hEGF was obtainable only in formalin-fixed sections using the monoclonal antibody against hEGF. In pleomorphic adenomas, positive hEGF staining was seen on the luminal side of tumors and in cells of ductal origin; no reactivity was present on the outer side of tumors or in cells of myoepithelial origin. Occasionally, long, spindle-shaped tumor cells and chondroidally changed tumor cells also exhibited positive staining for hEGF.

Histochemical studies of obstructive adenitis in human submandibular salivary glands. II. Lectin binding and keratin distribution in the lesions.

Lectin-binding profiles and keratin distribution in obstructive adenitis of human submandibular glands (SMGs) are reported and compared those of normal SMGs. Histologically, obstructive changes in the SMGs included acinar atrophy, duct-like structure formation in the early stage, and disappearance of acinar cells and dilation of ductal segments in the later, chronic stage. The following lectins were used: Con A (Glc, Man), PNA(Gal, GalNAc), RCA-I(Gal), DBA(GalNAc), SBA(Gal, Gal-NAc), UEA-I(alpha-L-Fuc) and WGA(GlcNAC, NeuNAc). Lectin staining in atrophic acinar cells was usually reduced except for SBA binding and was irregularly distributed in altered acinar and ductal epithelia. Binding of DBA and UEA-I lectins were particularly intense along the luminar borders of ductal segments in the lesions. Immunohistochemically detectable keratins were characterized by intense staining in atrophic acinar cells and in all the ductal segments, whereas normal acinar cells, either serous or mucous, were negative.

Histochemical studies of obstructive adenitis in human submandibular salivary glands. I. Immunohistochemical demonstration of lactoferrin, lysozyme and carcinoembryonic antigen.

Immunohistochemical detection of lactoferrin (LF), lysozyme (LZ) and carcinoembryonic antigen (CEA) was made in obstructive adenitis of the submandibular glands. Atrophic and altered acinar cells in the early stage of the lesion stained strongly for LF, whereas they were unreactive or stained slightly for LZ. Ductal cells usually stained for LZ. Staining for CEA was strong and irregularly distributed in altered acinar cells. Duct-like structures and dilated ductal segments in the chronic stage were generally negative for LF, LZ and CEA. Secretory components in luminal cavities gave abundant staining for LF, LZ and CEA. Histocytes which infiltrated into the connective tissue in the later stage showed a positive LZ reaction.

Characterization of cells in salivary gland lesions by immunohistochemical identification of carcinoembryonic antigens.

Immunohistochemical demonstration of carcinoembryonic antigen (CEA) was reported in normal salivary glands and in pathologic lesions. Staining patterns of CEA and nonspecific cross-reacting antigen-absorbed CEA (NCAa-CEA) were compared. Normal salivary glands disclosed positive staining by CEA on border and luminal sides of acinar cells and occasionally in components secreted into ductal spaces with both antigens used. Chronic obstructive lesions displayed an intense CEA staining in ductlike structures and in material secreted into their lumina in the two antigens used. Pleomorphic adenoma exhibited varying intensities of CEA in neoplastic epithelial cells of ductal structures. In contrast, they showed a slight staining reaction to NCAa-CEA. Squamous-cell carcinomas showed a strong CEA reaction, whereas they showed no reaction or a trace reaction to NCAa-CEA. Positive staining to CEA in squamous neoplastic lesions was related to nonspecific reacting antigens.