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PubMed1996

Multiple pleomorphic adenomas arising in the parotid and submandibular lymph nodes.

We report rare case of multiple pleomorphic adenomas arising in the parotid and submandibular lymph nodes of a 21-year-old man. These tumours were surrounded by lymphoid tissue which was almost identical to that of the cortex of lymph node. The possibility of metastasizing pleomorphic adenomas was discounted because the mitotic activity was low and there were no signs of infiltration. Heterotopic salivary gland tissue was also found in the lymph nodes that contained the tumours, and each tumour expressed a similar immunohistochemical staining pattern to that of the salivary gland tissue. These findings indicate that these pleomorphic adenomas probably arose from the salivary gland tissue within the lymph nodes.

Adenoma, Pleomorphic↗
PubMed1996

Surgical management of pleomorphic adenomas of the parotid gland: a follow-up study of three methods.

PURPOSE: This retrospective study evaluated data pertaining to history, symptoms, diagnosis, and mode of therapy of patients treated for pleomorphic adenoma of the parotid gland. PATIENTS AND METHODS: The records of 475 patients were reviewed. Follow-up was done by questionnaires sent to the referring doctor. RESULTS: The total rate of recurrence was 0.9% after 475 operations for pleomorphic adenoma of the parotid gland. One recurrence (0.7%) was reported for the group with superficial parotidectomy and none for the group with total parotidectomy. The rate of postoperative side effects was also low. The facial nerve was affected in 1.4% after superficial parotidectomy, and in 3.3% after total parotidectomy. CONCLUSION: The results of this follow-up study show that superficial parotidectomy for pleomorphic adenoma located in the superficial lobe of the parotid gland provides adequate therapy and generally avoids recurrence and side effects.

Adenoma, Pleomorphic↗
PubMed1993

Immunohistochemical expression of tenascin in normal human salivary glands and in pleomorphic adenomas.

The presence of the extracellular matrix glycoprotein tenascin was studied immunohistochemically in normal human salivary glands and in pleomorphic adenomas. Its expression was compared to that of fibronectin, and type IV collagen. In the normal salivary gland, tenascin was found with interruptions in periductal tissues, and continuously in blood vessels, fat cells and around nerve bundles. In pleomorphic adenoma, tenascin was detected surrounding the clusters of epithelioid cells, in areas with a myxoid and a chondroid matrix, and around some myoepithelial cells as a halo. As compared to fibronectin, there is a similar location of tenascin and fibronectin around tumor cell clusters but not in myxoid and chondroid matrices. Fibronectin was found around the cells in chondroid matrix. In conclusion, tenascin is not only found in malignant tumors but also in benign tumors such as pleomorphic adenoma. The presence of tenascin as a halo around myoepithelial cells suggests a role of these cells in development of myxoid and chondroid matrices.

Adenoma, Pleomorphic↗
PubMed1994

Distribution of the VLA family of integrins in normal salivary gland and in pleomorphic adenoma.

The extracellular matrix (ECM) and the alterations in tumour stroma affect the biologic behaviour of tumours. These interactions are, at least in part, mediated by the integrin superfamily. In this study we examined the immunohistochemical expression of the "very late activation" (VLA)-integrins in pleomorphic adenomas and in the corresponding normal tissues. Normal salivary gland expresses integrins in the myoepithelial cells (MEC) and in the basal and dark cells of ducts. This pattern is retained in pleomorphic adenoma. Regardless of the straining intensity, these tumour cells have a VLA expression similar to normal basal and dark cells, with only a few cells bearing MEC characteristics. We suggest that the tumour cells of pleomorphic adenoma have a common origin but show different stages of differentiation. Only cells bearing basement membrane (BM)-associated material form typical tubulo-ductal structures.

Adenoma, Pleomorphic↗
PubMed1990

Expression of c-erbB-2 protein detected in adenocarcinoma arising from parotid pleomorphic adenoma.

The c-erbB-2 proto-oncogene is known to encode a 185,000 molecular weight glycoprotein. This protein has been detected immunohistochemically in several human adenocarcinomas, suggesting that it may play a role in the development of these malignancies. In the otolaryngological field none of the adenocarcinomas expressing c-erbB-2 protein has yet been described. In this article we presented a case of parotid adenocarcinoma expressing the c-erbB-2 protein. In this case the adenocarcinoma was thought to have originated from pleomorphic adenoma. Immunohistochemically, the adenocarcinoma cells were stained and the remaining pleomorphic adenoma cells were not stained by polyclonal antibody against the c-erbB-2 protein. The expression of c-erbB-2 protein may have been related to the malignant development of the pleomorphic adenoma.

Adenocarcinoma↗
PubMed2002

Intracapsular carcinoma ex pleomorphic adenoma. Report of a case with unusual metastatic behaviour.

Intracapsular carcinomas ex pleomorphic adenoma are exceedingly rare salivary glands tumours, known to have a benign clinical behaviour with metastatic unrecognised potential. We report a case of a 57-year-old female patient presenting with a typical example of intracapsular carcinoma ex pleomorphic adenoma of the parotid gland and evidence of ipsilateral cervical lymph node metastases two years before. The behaviour of this unique case illustrates the disputed malignancy of carcinomas arising within encapsulated pleomorphic adenomas.

Adenoma, Pleomorphic↗
PubMed1989

Clear cell carcinoma arising in pleomorphic adenoma of the minor salivary gland.

Malignant change arising in pleomorphic adenoma of the salivary glands is uncommon, with a reported incidence of 2-10 per cent. Only one case where a pleomorphic adenoma became a clear cell carcinoma appears to have been published in the English literature. An additional case of clear cell carcinoma arising in pleomorphic adenoma of a minor salivary gland is reported and the relevant literature discussed.

Adenocarcinoma↗
PubMed1997

Co-existing pleomorphic and tubular basal cell adenomas of the parotid gland.

We report a hitherto undescribed case of co-existence of a pleomorphic adenoma and a tubular basal cell adenoma affecting the superficial lobe of the left parotid gland of a 53-year-old man. The histology of the pleomorphic adenoma is also of interest in that the prominent adipose metaplasia of its myxoid stroma yielded an appearance reminiscent of myxoid lipoma. The tubular basal cell adenoma showed gross cystic change, and its solid portion consisted of closely packed tubules lined by double layers of cuboidal cells with little intervening stroma. Unlike Warthin's tumour and membranous basal cell adenoma, both pleomorphic and tubular basal cell adenomas exhibit no propensity towards multicentricity or bilaterality. We, therefore, believe that their co-existence in the superficial lobe of the parotid gland of our patient is a mere coincidence rather than association.

Adenoma↗
PubMed2003

Pleomorphic adenoma of the submandibular salivary glands with marked ossification.

This article describes an unusual case of pleomorphic adenoma arising in the submandibular salivary glands that was associated with marked ossification. CT scan showed an irregular high-density mass in the left submandibular region. Histologic examination of the resected mass revealed a well-circumscribed pleomorphic adenoma with chondroid tissue intermingled with glandular and trabecular epithelial components. Irregularly formed osseous tissue was present in the chondroid tissue. The osseous tissue showed bone matrix on von Kossa's staining. Alkaline phosphatase expression was restricted to the vicinity of osseous tissue. Tartrate-resistant acid phosphatase-positive osteoclasts were observed at the periphery of the osseous tissue. CD34 staining demonstrated many microvascular vessels in both the chondroid and osseous tissues. We conclude the osseous tissue in pleomorphic adenoma was bone in nature, and via the process of endochondral ossification most likely depended on angiogenesis.

Acid Phosphatase↗
PubMed1996

Immunohistochemical study of c-erbB-2 expression in carcinoma ex-pleomorphic adenoma.

A series of 19 cases of carcinoma ex-pleomorphic adenoma was studied for the immuno-expression of c-erbB-2 oncoprotein. Twelve tumours showed a malignant component with only one histological type; in the remaining seven there was co-existence of areas of various carcinoma types, adenocarcinoma NOS being the most frequent. Membranous c-erbB-2 reactivity was found in 21.1% of the cases, all corresponding to high-grade adenocarcinomatous areas. The low-grade carcinoma types that formed the malignant mixed tumours components were negative. Benign pleomorphic adenoma areas, either adjacent or intermingled with carcinomatous areas, were also consistently negative, proving that c-erbB-2 accumulation is associated with the acquisition of the malignant phenotype. The finding of a preferential association between c-erbB-2 overexpression and high-grade malignant mixed tumour may indicate prognostic implications for the oncogene protein and may also be indicative of its specific relationship with the putative pathway of malignant transformation in pleomorphic adenomas.

Adenocarcinoma↗
PubMed2001

Pleomorphic adenoma of the parotid gland with extensive bone formation.

We report an unusual case of pleomorphic adenoma with extensive bone formation, occurring in the parotid gland of a 58-year-old Japanese man. The tumor was a well-circumscribed mass that measured 20 x 20 x 15 mm and contained extensive bone formation. Histologically, most of the tumor was composed of bone and chondroid tissues. The bone formation with a marrow-like structure occupied half the volume of the tumor. The chondroid tissues merged continuously into bone tissues. The bone tissue seemed to be formed within areas of chondral tissue by a process of enchondral ossification. Except for the unusual amount of large bone formation, the tumor showed histology of pleomorphic adenoma, particularly at the periphery of the tumor. These histological findings suggest the possibility of extensive enchondral ossification in pleomorphic adenoma.

Adenoma, Pleomorphic↗
PubMed2000

Molecular evidence that the stromal and epithelial cells in pleomorphic adenomas of salivary gland arise from the same origin: clonal analysis using human androgen receptor gene (HUMARA) assay.

Salivary gland pleomorphic adenomas are characterized by a biphasic growth of "epithelial" and "stromal" regions. The "epithelial" region is a compactly organized mixture of both luminal and nonluminal cells, whereas the stromal region is composed predominantly of the nonluminal cells. Using the polymerase chain reaction (PCR)-based HUMARA assay on DNA from formalin-fixed, paraffin-embedded tissues from pleomorphic adnomas of female patients, we intend to clarify the clonal relation between the luminal and nonluminal cells and the clonal nature of the morphologically diverse nonluminal cells in this tumor. HUMARA, the human androgen receptor gene, is located on the X chromosome and contains a segment of polymorphic CAG tandem repeats in exon 1. Several methylation-sensitive HhaI restriction sites are located 5' to these CAG repeats. It is an ideal tool to study clonality of female tissues by examining the methylation pattern. Of the 13 cases analyzed, 3 were homozygous at the HUMARA locus and therefore noninformative. The remaining 10 cases were informative. All 10 cases showed a monoclonal pattern in the stromal area, indicating that the morphologically diverse nonluminal cells are monoclonal. Eight of the 10 cases showed monoclonality in the "epithelial" areas, suggesting a common clonality between luminal and nonluminal cells. Of the remaining 2 samples, 1 was polyclonal for the "epithelial" region, and the other was not amplifiable. Our data provide the first molecular evidence that the luminal and nonluminal cells in pleomorphic adenomas arise from the same clone in most cases, and the morphologically diverse nonluminal cells are monoclonal.

Adenoma, Pleomorphic↗
PubMed1994

[Pleomorphic adenoma of the maxillary sinus].

Pleomorphic adenoma is the most common benign tumour of the salivary glands, especially the parotid gland. In the present paper we introduce the rare case of a pleomorphic adenoma of the maxillary sinus in a 82-year-old man who was referred to our outpatient clinic with nasal obstruction and occasional events of nose bleeding. Thorough investigation, using endoscopy and computed tomography, revealed a mass extending from the left maxillary sinus to the nasal cavity; the tumour was removed surgically; pathological examination showed a pleomorphic adenoma with no signs of malignancy.

Adenoma, Pleomorphic↗
PubMed2002

Subcutaneous pleomorphic adenomas in two different areas of the face.

A 41-year-old woman developed two subcutaneous pleomorphic adenomas on her face. Pleomorphic adenoma usually arises as a benign tumour of a major salivary gland and often develops multifocally within the gland. These two pleomorphic adenomas originated in the subcutaneous layer of the face, also multifocally. They were excised, she made a good recovery, and she had no signs of recurrence a year later.

Adenoma, Pleomorphic↗
PubMed1990

Pleomorphic adenoma (benign mixed tumor) of the breast. An immunohistochemical, flow cytometric, and ultrastructural study and review of the literature.

Pleomorphic adenoma (or benign mixed tumor) of the breast is a rare benign neoplasm that might be misinterpreted both clinically and pathologically as a malignant tumor. The authors present an additional case of this unusual lesion studied by immunohistochemistry, electron microscopy, and flow cytometry. A 77-year-old white woman presented with a 2-cm, nontender, mobile, calcified, right subareolar mass suggestive of a fibroadenoma. Microscopically, the tumor resembled a pleomorphic adenoma occurring in salivary glands. Positive immunostaining for S-100 protein, cytokeratin, and muscle-specific actin, as well as the ultrastructural presence of intermediate filaments with dense bodies and intercellular junctions, supported the predominant myoepithelial cell differentiation within the tumor, whereas the epithelial cell component stained only with cytokeratin and contained formed lumina with surface microvilli. The DNA pattern was diploid. The patient is alive and well 14 months after surgery. The authors' findings confirm that pleomorphic adenoma of the breast is a benign neoplasm in which myoepithelial cell proliferation plays a major role in tumorigenesis.

Adenofibroma↗
PubMed1997

Huge pleomorphic adenoma of the upper retromolar area.

The case of a 41-year-old female is described wherein a minor salivary gland pleomorphic adenoma originating in the right retromolar area had extended into the infratemporal fossa and enlarged to 5 x 6 x 12 cm. The patient first became conscious of the mass as a slight swelling of the buccal mucosa when she was about 30 years of age, and the swelling since then had gradually gained in prominence. Preoperative computed tomography scan demonstrated a well-circumscribed mass occupying the right infratemporal fossa and medially displacing the pterygoid laminas. The mass was easily removed without much bleeding and no recurrence has been detected for 4 years. The incidence of pleomorphic adenoma originating in the retromolar area, the size of minor salivary gland pleomorphic adenomas at the time of diagnosis, and the treatment of choice are discussed.

Adenoma, Pleomorphic↗
PubMed2001

Surgical techniques in the treatment of pleomorphic adenoma of the parotid gland: our experience and review of literature.

This paper presents a retrospective study carried out on a sample of 100 patients affected by pleomorphic adenoma of the parotid gland and treated at the Department of Maxillofacial Surgery at the University of Rome "La Sapienza" between January 1, 1989 and December 31, 1997. For the diagnosis of this neoformation, cytological tests were performed on material taken from the neoformation using fine needle aspiration and ultrasound scan. In some selected cases, a CT examination of the head and neck with medium contrast or Nuclear Magnetic Resonance (NMR) was carried out. This study sets out to examine the most suitable treatment to be followed for the removal of the pleomorphic adenoma of the parotid gland. In 56 cases the patients underwent a superficial, conservative parotidectomy. Forty one patients had a total parotidectomy with the facial nerve left intact and one patient had a total parotidectomy where the marginal mandibular nerve of the facial nerve was damaged. The remaining two patients involved in the study were suffering from a recurrent pleomorphic adenoma and in these two cases a total parotidectomy was performed where the facial nerve was killed. The removal of the cranial nerve VII in these patients proved necessary because the nerve fibers had adhered to the surrounding scar tissue of the tumor, either after previous surgery or due to repeated chronic phlogosis of the gland.

Adenoma, Pleomorphic↗