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Multiple expression of keratins, vimentin, and S-100 protein in pleomorphic salivary adenomas.

Immunohistochemical staining for S-100 protein and the intermediate filaments keratin and vimentin, was made in 41 salivary adenomas. In pleomorphic adenomas, great heterogeneity in the staining, as well as multiple and co-expressions of these proteins were found in the outer tumor cells of tubulo-ductal structures and modified myoepithelial cells, but not in the luminal tumor cells. All the outer tumor cells stained for S-100 protein, 97% for K8.12 keratin and 85% for vimentin. Of these cells, 29% showed multiple expression of K8.12 keratin, vimentin, and S-100 protein, and 17% showed co-expression of K8.12 and S-100 protein. Modified and neoplastic myoepithelial cells showed similar expressions of these proteins to those of outer tumor cells; myoepithelioma cells displayed the most complicated pattern, being positive for KL1, PKK1, and K8.12 keratins, vimentin and S-100 protein. In luminal tumor cells there was a heterogeneous expression of KL1 and PKK1 in 82%, and of KL1, PKK1, and K8.12 in only 14.7%. Based on the immunohistochemical findings obtained with different monoclonal antibodies in pleomorphic salivary adenomas, outer tumor cells may be derived from ductal basal cells and luminal tumor cells from intercalated duct cells.

Adenoma, Pleomorphic↗

Abundant dendritic cells express HLA-DR in pleomorphic adenomas.

Most pleomorphic adenomas were found to contain abundant dendritic cells (DC) with major histocompatibility complex (MHC) class II (HLA-DR) expression. Their immunohistochemical staining features were suggestive of dendritic histiocytic cells. Extensive phenotypic characterization by two-colour immunofluorescence staining for various cell markers was performed. The DC expressed both HLA class I and II determinants, vimentin, S-100 protein, and various monocyte-related markers (10G11, 3D10, 7G5 or CD11a, 8C2) but were negative for leucocyte common antigen (CD45), Leu-6 (CD1), and the myelomonocytic L1 antigen. Characterization of HLA-DR positive DC isolated by an immunomagnetic bead method confirmed the immunohistochemical staining pattern that corresponds to the phenotype of interdigitating cells. Morphological and immunological implications of the abundant presence of these cells in pleomorphic adenomas are discussed.

Adenoma, Pleomorphic↗

Recurrent pleomorphic adenoma of the head and neck.

We reviewed the clinical and imaging files of 15 patients with pathologically confirmed recurrent pleomorphic adenomas of the head and neck. The primary tumours were in the lacrimal gland (1 case), cheek (2), palate (5), parotid gland (4), and submandibular gland (3). Recurrence was generally late, with an average of 14.9 years between initial surgery and recurrence. Multiple recurrent tumours, measuring 5-50 mm were found in eight patients. In all palatal cases recurrence was large and solitary. Most recurrent pleomorphic adenomas were well delineated with smooth margins, like most primary tumours. Irregularity of the margins was seen in four patients. In four of the five tumours of the palate and in the orbital lesion, the recurrent tumours caused bone destruction, thus mimicking malignant lesions. Irregular-margined recurrences seem to be rather small and found among multiple recurrent nodules.

Adenoma, Pleomorphic↗

[Juvenile pleomorphic parotid adenoma of embryonal structure].

Juvenile pleomorphic adenoma of the parotid gland represents an extremely rare tumour entity and is comparable to congenital tumours of the salivary glands concerning its embryonal structure. The clinical detection of the tumour in a 7-year-old girl does not exclude that the tumour had developed either earlier or immediately after the birth. The high cellularity and the evidence of primitive epithelial and myoepithelial cellular structures do not justify its classification as a malignant tumour. However the presence of embryonal tissue structures associated with the end of the third month of embryogenesis is characterized by more solid cell formations in partly verticulate arrangement. The absence of further differentiation into lobular structures and differentiated duct or acinic cell formations may be due to cell arrest. Differential diagnosis of juvenile pleomorphic adenoma must distinguished it from other congenital salivary gland tumours (e.g. congenital basal cell adenoma, hybrid basal cell adenoma-adenoid cystic carcinoma, sialoblastoma, salivary gland anlage tumour.

Adenoma, Pleomorphic↗

[Pleomorphic adenoma (mixed tumor) of the external auditory canal. Differential diagnosis of the tumors of the ceruminal glands].

A tumor was removed from the right external auditory canal of a 69-year old female patient. The histopathological and immunhistochemical evaluation revealed a pleomorphic adenoma (mixed tumor). The differential diagnosis of the tumors derived from the ceruminal glands, their clinical and prognostic implications as well as the histogenesis of pleomorphic adenomas in this localization are discussed.

Adenoma, Pleomorphic↗

Pleomorphic adenoma of the parotid gland: a 13-year experience of consequent management by lateral or total parotidectomy.

Optimal surgical management of parotid pleomorphic adenoma is important because of a considerable risk of tumour recurrence and complications. Our series of primary surgery cases with standardised parotidectomy technique in a university hospital were evaluated. Medical records of 295 patients treated from 1987 to 1999 were reviewed, and 171 patients answered a questionnaire about long-term sequelae. Sixty-two patients reporting major complications were re-examined in the hospital. At a mean follow-up of 8 years, one patient (0.6%) re-appeared with a recurrence. Twenty-four percent left the hospital with a partial and 3% with a complete paresis. Only 5% developed a permanent partial paresis, whereas a permanent total paresis was not seen. Half of the patients indicated gustatory sweating, but treatment was required in only 6%. Other major permanent complications were not seen. Treatment of pleomorphic adenoma by standardised parotidectomy in a university hospital demonstrates favourable results with low perioperative and long-term morbidity, as well as minimal risk of tumour relapse.

Adenoma, Pleomorphic↗

Concurrent primary Hodgkin's lymphoma and recurrent pleomorphic adenoma of the ipsilateral parotid gland: report of a rare case.

The synchronous occurrence of two histologically different and morphologically distinct tumours in a single parotid gland is an exceptionally rare and probably coincidental event. We have recently experienced such a case initially suspected of being a recurrent pleomorphic adenoma. Superficial parotidectomy, however, revealed two separate masses. Postoperative histopathological examination diagnosed the presence of a pleomorphic adenoma with a concurrent primary parotid gland Hodgkin's lymphoma arising from an intraglandular lymph node. The management of this case is presented along with a brief review of the literature concerning the evaluation and management of this rare entity.

Adenoma, Pleomorphic↗

Pigmented pleomorphic adenoma, a novel melanin-pigmented benign salivary gland tumor.

This paper reports a pleomorphic adenoma with grossly visible pigmentation resulting in the macroscopic appearance of melanotic lesion in a 33-year-old Japanese male. In addition to the characteristic histopathological features of a benign pleomorphic adenoma, variously formed and -sized cells, many of which were considered to be melanocytes, containing melanin pigment in their cytoplasm, were distributed in the epithelial component. In addition, melanin pigment was deposited in tumor cells of duct structures. Furthermore, condensed secretory substances with marked pigmentation were frequently seen in the tubular lumina. Perusal of the English language literature revealed only two cases of parenchymal pigmentation of salivary gland tumors: both were mucoepidermoid carcinoma. The possible histogenesis of melanocytes in the salivary gland lesions is discussed, though no firm conclusion could be drawn.

Adenoma, Pleomorphic↗

Carcinoma ex-pleomorphic adenoma of the breast. Report of three cases suggesting a relationship to metaplastic carcinoma of matrix-producing type.

Three cases of carcinoma ex-pleomorphic adenoma of the breast are reported. Patients were 82, 60 and 56 years old and presented with a breast lump. All tumours showed areas of pleomorphic adenoma adjacent to typical areas of malignant transformation. These cases add to the spectrum of tumours shared by breast and salivary gland. The relationship between these neoplasms and metaplastic carcinoma of matrix-producing type is discussed.

Adenoma, Pleomorphic↗

"Hyaline cells" in pleomorphic adenoma of salivary gland origin.

Fifty-two cases of pleomorphic adenoma of minor salivary gland origin and seventy-two cases of pleomorphic adenoma of major salivary gland origin were examined for the presence of hyaline cells (plasmacytoid cells). Hyaline cells were found in 38 percent of the minor salivary gland cases and 21 percent of the major salivary gland cases. When stained with hematoxylin and eosin, the hyaline cells exhibited an eccentric nucleus and a striking homogenous, ground-glass, eosinophilic cytoplasm. At the ultrastructural level, the cytoplasm of the hyaline cells was closely packed with intermediate-sized filaments having no apparent orientation. It is suggested that the hyaline cells are modified myoepithelial cells.

Adenoma, Pleomorphic↗

Immunolocalization of keratins in salivary gland pleomorphic adenoma using monoclonal antibodies.

Monoclonal antibodies to keratins (KL1 and PKK1) were tested on paraffin sections in forty cases of pleomorphic adenoma from salivary glands. Squamous cells in the epidermis were positive for KL1, except for the basal cells, which were positive for PKK1. In normal salivary glands, ductal cells were positive for KL1 and PKK1 keratins, whereas KL1 staining of the large excretory ducts was weaker than that of PKK1. Myoepithelial cells were positive only for KL1. In pleomorphic adenoma, the following reactions were noted: a positive staining for KL1 and PKK1 was present in the inner layer of cells within tubular and ductlike structures, a markedly positive staining for KL1 was present in squamous metaplastic cells, and a negative staining reaction with KL1 and PKK1 in spindle-shaped tumor cells was observed within the outer layer. Spindle-shaped or fibroblast-like cells in the stroma, probably myoepithelial in origin, showed an irregular staining expression for KL1 and PKK1.

Adenoma, Pleomorphic↗

Multiple synchronous bilateral Warthin's tumors of the parotid glands with pleomorphic adenoma. Case report and review of the literature.

A case of multiple bilateral synchronous Warthin's tumors of the parotid glands with a simultaneous pleomorphic salivary adenoma in one patient is presented. This case appears to be unique. Only three previous cases of multiple synchronous bilateral Warthin's tumors have been reported. The occurrence of salivary tumors of different histologic types in the same patient is also rare. Twenty cases of Warthin's tumor that occurred with pleomorphic salivary adenoma were found in our review of the literature. However, none of these represented synchronous bilateral multiple Warthin's tumors.

Adenolymphoma↗

Cytogenetic investigations on a cell line derived from a carcinoma arising in a salivary gland pleomorphic adenoma.

This article discusses the results of cytogenetic investigations of a cell line derived from a malignant tumor arising in a benign salivary gland pleomorphic adenoma. Initial karyotypic studies became possible with cells of the second in vitro passage and revealed the existence of hypertetraploidy. Furthermore, a marked polysomy 7 and a translocation involving 12q13-15, a breakpoint also frequently seen in benign pleomorphic adenomas, were noteworthy. During long term culture, the number of chromosomes per cell decreased as well as the number of copies of chromosome 7. Cell tumorigenicity was proved by heterotransplantation to nude mice. The resulting tumors were karyotyped again. No significant changes of the chromosome number or of the degree of polysomy 7 were found compared to the cells before heterotransplantation. In contrast, the cells from the nude mice tumors showed a remarkable number of different isochromosomes probably indicating an unknown factor supporting the generation of isochromosomes. The consistent presence of the t(12;?)(q13-15;?) makes the cell line well suited for molecular studies of this breakpoint region.

Adenoma, Pleomorphic↗

Cytogenetic subtyping of 220 salivary gland pleomorphic adenomas: correlation to occurrence, histological subtype, and in vitro cellular behavior.

Based on the hypothesis that three main cytogenetic subtypes of salivary gland pleomorphic adenomas can be distinguished which may also represent different etiologic entities, we investigated whether these subtypes correspond to clinical, histologic, or biologic features of 220 tumors karyotyped (including 117 tumors with detailed clinical history and histologic subtyping). The following results were obtained. As compared with the group of patients showing salivary gland pleomorphic adenomas with an apparently normal karyotype, the patients in the "8q12-group" were significantly younger (51.1 years versus 39.3 years, p < 0.001). The distribution of histologic subtypes also showed highly significant differences between the groups. Whereas the breakpoint in the 8q12 group was always mapped to a single band, no exact localization of the breakpoint in the group of tumors showing chromosome number 12 abnormalities was possible. In most cases, however, the breakpoints were clustered to 12q15. Finally, all tumors with 8q12 breakpoints showed a characteristic in vitro cellular morphology which was also observed in a few tumors with an apparently normal karyotype but in none of the tumors with the 12q13-15 breakpoint.

Adenoma, Pleomorphic↗

Identification of the chromosome 12 translocation breakpoint region of a pleomorphic salivary gland adenoma with t(1;12)(p22;q15) as the sole cytogenetic abnormality.

Cell line Ad-312/SV40, which was derived from a primary pleomorphic salivary gland adenoma with t(1;12)(p22;q15), was used in fluorescence in situ hybridization (FISH) analysis to characterize its translocation breakpoint region on chromosome 12. Results of previous studies have indicated that the chromosome 12 breakpoint in Ad-312/SV40 is located proximally to locus D12S8 and distally to the CHOP gene. We here describe two partially overlapping yeast artificial chromosome (YAC) clones, Y4854 (500 kbp) and Y9091 (460 kbp), which we isolated in the context of a chromosome walking project with D12S8 and CHOP as starting points. We present a composite long-range restriction map encompassing the inserts of these two YAC clones and show by FISH analysis that both YACs span the chromosome 12 breakpoint as present in Ad-312/SV40 cells. Subsequently, we have isolated cosmid clones corresponding to various sequence-tagged sites (STSs) mapping within the inserts of these YAC clones. These included cRM51, cRM69, cRM85, cRM90, cRM91, cRM110, and cRM111. In FISH studies, cosmid clones cRM85, cRM90, and cRM111 appeared to map distally to the chromosome 12 breakpoint, whereas cosmid clones cRM51, cRM69, cRM91, and cRM110 were found to map proximally to it. These results assign the chromosome 12 breakpoint in Ad-312/SV40 to a DNA region of less than 165 kbp. FISH evaluation of the chromosome 12 breakpoints in five other pleomorphic salivary gland adenoma cell lines indicated that these are located proximally to the one in Ad-312/SV40, at a distance of more than 0.9 Mbp from STS RM91. These results, while pinpointing a potentially critical region on chromosome 12, also provide evidence for the possible involvement of 12q13-q15 sequences located elsewhere.

Adenoma, Pleomorphic↗

Involvement of p53 mutation in the development of human salivary gland pleomorphic adenomas.

We examined the status of the p53 mutation, a putative tumor suppressor gene, as well as the expressions of myc and mos oncogene products in human salivary gland pleomorphic adenoma cells in culture derived from four individuals using techniques which enabled selective and favourable growths of tumor cells. Culture techniques empolyed in this study consisted of type I collagen gel-coated dishes and serum-free medium as substrates and growth medium, respectively. Cells grown under above conditions were subjected to the analyses of p53, myc and mos expression. When analyzed by both immunocytochemical staining and immunoblot, mutant forms of p53 specifically detected by PAb240 were observed in three of 4 cases. However, none of the 4 cases expressed myc and mos oncogene products. These results may imply a role for p53 mutation in the development of human salivary gland pleomorphic adenomas.

Adenoma, Pleomorphic↗

Long-term results of local excision and radiotherapy in pleomorphic adenoma of the parotid.

Three hundred and eleven patients with primary pleomorphic salivary adenoma of the parotid gland seen between 1950 and 1971 are reviewed. All were managed by a combination of surgery, usually local excision, and irradiation. The minimum follow-up is 10 years. Recurrence rates at 0-5 years and 5-10 years were 1 and 1.5%, respectively, and all recurrences in this period were histologically or clinically benign. This recurrence rate is similar to those reported after superficial parotidectomy. After 10 years, however, the recurrence rate rose, becoming maximal at 15-20 years (4%) and yielding a cumulative risk of recurrence of 8.0% at 20 years. The late recurrences were predominantly malignant tumors. One tumor was probably radiation-induced; the remainder were compatible with spontaneous malignant transformation of benign pleomorphic adenoma, although radiation may have increased the incidence. In the absence of a comparable purely surgical series, this cannot be determined. The recommendation is made that the management of these tumors should be primarily surgical with irradiation reserved for patients presenting surgical difficulties. In addition, prolonged follow-up is necessary since there is a significant incidence of late recurrence and such recurrence may be more likely to be malignant regardless of the primary form of management.

Adenoma, Pleomorphic↗