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PubMed1987

Oncocytic pleomorphic adenoma of the parotid gland.

A rare case of salivary gland pleomorphic adenoma, in which the majority of cells were oncocytic, is reported. The patient, a 53-year-old man, presented with a parotid gland mass that was otherwise asymptomatic. Surgical treatment consisted of a superficial parotid lobectomy. The specimen was prepared in standard fashion and studied by light and electron microscopy. The microscopic features were characteristic of salivary gland pleomorphic adenomas, however, both epithelial and "mesenchymal" elements were oncocytic. Such changes may occur focally in pleomorphic adenomas, but we were unable to find documentation of a wholly oncocytic variant in a review of the medical literature. From our clinical data and previous reports of pleomorphic adenomas with focal oncocytosis, it is concluded that such changes likely do not alter prognosis in affected patients. The possible significance of this lesion in regard to the histogenesis of salivary gland pleomorphic adenomas is discussed.

Adenoma, Pleomorphic↗
PubMed2002

Alterations of the INK4a-ARF gene locus in pleomorphic adenoma of the parotid gland.

Pleomorphic adenomas of the parotid gland are benign tumours composed of epithelial and mesenchymal cells. The INK4a-ARF (CDKN2A) locus on chromosome 9p21 encodes two tumour suppressor proteins, p16(INK4a) and p14(ARF), which act as upstream regulators of the Rb-CDK4 and p53 pathways. To study the contribution of each pathway in pleomorphic adenomas, this study analysed alterations of p14(ARF), p16(INK4a), p53, and pRb in these tumours. After microdissecting the different histological components, 42 pleomorphic adenomas of the parotid gland were analysed for INK4a-ARF inactivation by DNA sequence analysis, methylation-specific PCR (MSP), restriction enzyme-related polymerase chain reaction (RE-PCR), mRNA expression, microsatellite analysis, and immunohistochemistry. In addition, microdeletion of p14(ARF) and p16(INK4a) were assessed by differential PCR. The status of p53 and Rb was examined by direct sequencing and immunohistochemistry. Using microdissection, it was possible to examine the tumour components, i.e. epithelial, mesenchymal, and transitional, separately after immunohistochemical identification. Methylation of p14(ARF) was found in 1/42 cases and alterations of p16(INK4a) occurred in 12/42 of pleomorphic adenomas, which correlated with loss of mRNA transcription. Microdeletions or specific mutations of either exon were not detected. Methylation was detected exclusively in the epithelial and transitional components and not within the mesenchymal part of the tumour. p53 mutations were detected in 4/42 adenomas, also occurring solely in the epithelial components of the tumours. pRb was detected immunohistochemically in 40/42 adenomas. In normal, corresponding parotid tissue, p14(ARF), p16(INK4a), p53, and pRb alterations were not observed. The observation that alterations of p14(ARF) and p16(INK4a), and also p53 mutations, occurred exclusively in the epithelial and transitional components of pleomorphic adenoma supports the theory that these areas are prone to malignant transformation to carcinoma in adenoma.

Adenoma, Pleomorphic↗
PubMed1989

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.

Adenoma, Pleomorphic↗
PubMed1998

[Problems in diagnosis and therapy of carcinoma in stroma-abundant pleomorphic adenoma of the parotid gland].

The case is reported of a 27-year-old patient who developed multiple recurrences of a carcinoma arising from richly stromal pleomorphic adenoma of the parotid gland over 13 years. Originally the tumor was classified as a benign pleomorphic adenoma because there were no cytological characteristics of malignancy. Later on the diagnosis had to be modified to that of a carcinoma arising from a pleomorphic adenoma because of the infiltrating growth pattern of the tumor. A multicentric local recurrence and metastases on the left side of the neck supported the correct diagnosis. This case demonstrates that, beside the classic cytological criteria of malignancy invasion and penetration of the capsule can be decisive for the diagnosis of malign transformed pleomorphic adenoma. Treatment and prognosis of salivary gland tumors assume a clear determination of their diguity. The unusual course in this case of a pleomorphic adenoma originally diagnosed as benign demonstrates the importance of regular follow-up.

Adenoma, Pleomorphic↗
PubMed1994

Familial occurrence of pleomorphic adenoma.

Pleomorphic adenoma is the most common neoplasm found in the parotid gland. The familial occurrence of any salivary gland neoplasm is rare. There are 8 previous reports in the literature of familial occurrence of salivary gland tumors. Two of these report the occurrence of pleomorphic adenoma of the parotid gland in siblings; all 4 patients were adults. We report here an 11-year-old male who presented with a left parotid mass and underwent parotidectomy. The mass proved to be a pleomorphic adenoma. His sister presented 9 years later at the age of 15 years with a similar mass also in the left parotid area. She underwent superficial parotidectomy which revealed the mass to be a pleomorphic adenoma. We believe these are the youngest siblings reported to date in which familial pleomorphic adenoma has occurred.

Adenoma, Pleomorphic↗
PubMed2005

Adenocarcinoma ex pleomorphic adenoma of the head and neck: Report of five cases.

OBJECTIVE: Adenocarcinoma ex pleomorphic adenoma is a rare tumor, and thus the management of the tumor has not been established. METHODS: The retrospective review of the clinical records at Okayama University was performed. RESULTS: We present five cases of adenocarcinoma ex pleomorphic adenoma of the head and neck, including a rare case with nasopharyngeal adenocarcinoma ex pleomorphic adenoma. There was no response to chemotherapy with nedaplatin and 5-FU, but the nasopharyngeal adenocarcinoma ex pleomorphic adenoma showed a remarkable regression after the administration of docetaxel. CONCLUSION: The combination therapy that includes docetaxel may be a promising treatment for adenocarcinoma ex pleomorphic adenoma of the head and neck.

Adenoma, Pleomorphic↗
PubMed2006

Atypical features in pleomorphic adenoma--a clinicopathologic study and implications for management.

Pleomorphic adenoma is the most common salivary gland neoplasm and infrequently undergoes malignant transformation. Carcinoma ex pleomorphic adenoma is typically an infiltrative neoplasm with features of cellular pleomorphism, high mitotic activity, peri-neural and vascular invasion. More recently, sub-groups of pleomorphic adenoma have been described exhibiting vascular invasion and features of malignancy without evidence of extra-capsular extension. There is little information in the literature regarding how these different histological variants influence clinical presentation and outcome following primary treatment. Following a review of 100 consecutive pleomorphic adenomas removed from the major salivary glands, 4 cases with atypical histological features were found. Three tumours exhibited features of dysplasia/carcinoma without evidence of extra-capsular invasion and a further case demonstrated benign vascular invasion. There were no clinical features suggestive of the atypical nature of these neoplasms, though fine needle aspiration cytology (FNAC) was suspicious of a malignancy in 2 cases and CT scan in 1 case. Patients underwent a superficial parotidectomy or submandibular gland excision based on the location of the lesion. All lesions were completely excised and there were no recurrences in this series.

Adenoma, Pleomorphic↗
PubMed1990

Metastasizing pleomorphic adenoma with myoepithelial cell predominance.

The biological behavior of pleomorphic adenomas (mixed tumors) of salivary gland origin is complex. Tumors with benign histologic features may exhibit recurrence and locally aggressive behavior especially after incomplete excision. A small percentage of pleomorphic adenomas have obvious malignant components in epithelial or in both epithelial and mesenchymal components and can metastasize. There are also rare case reports which appear to document typical pleomorphic adenomas of salivary gland with histologically identical visceral and lymph node metastases. Recently myoepithelial cell proliferation has been identified as a possible predictor of aggressive clinical behavior in otherwise histologically benign pleomorphic adenomas. We report such a parotid gland lesion with local recurrence and retroperitoneal spread. DNA-flow cytometry of cells from the paraffin-embedded primary and metastasis showed similar aneuploid populations. Aneuploidy appeared to reflect the malignant potential of this particular pleomorphic adenoma and suggests that DNA-flow cytometry of salivary gland tumors may yield important prognostic information.

Adenoma, Pleomorphic↗
PubMed1999

Lipomatous pleomorphic adenoma of the parotid gland. Classification of lipomatous tissue in salivary glands.

Lipomatous pleomorphic adenoma is an unusual subtype with a lipomatous stromal component of more than 90% of the tumour tissue. This special type of pleomorphic adenoma must be distinguished from other types of lipomatous tumours or non-tumourous lipomatosis of the salivary glands. Until now only two cases of lipomatous pleomorphic adenoma have been reported in the literature. We report of a 36-year old woman who developed a well circumscribed nodule measuring 3.5 x 2.5 x 2 cm in the right parotid gland. The cut surface was grey-yellowish. Histologically, more than 90% of the tumour tissue was fatty tissue with univacuolar adipocytes. The pleomorphic epithelial elements were duct-like cells forming small lumina and spindle-shaped myoepithelial cell with surrounding mucoid stroma. Components of pleomorphic adenoma were intermingled with mature adipose tissue which was more concentrated in the central portion of the adenoma. Some compressed epithelial cords in the adipose tissue formed a septa-like pattern. The differential diagnosis to other lipomatous tumours (lipoadenoma, lipoma) and to non-tumourous interstitial lipomatosis as well as the possible pathogenesis as metaplastic change or epithelial-mesenchymal transdifferentiation are discussed.

Adenoma, Pleomorphic↗
PubMed2002

Pleomorphic adenoma in nasal cavity: immunohistochemical study of three cases.

Intranasal pleomorphic adenoma is a rare neoplasm, and thus only one case report addressed immunohistochemical findings of this neoplasm. To define immunohistochemical features of intranasal pleomorphic adenoma, we studied three cases of the pleomorphic adenoma developed from the nasal septum. Subsequently, immunohistochemical reactivities of the tumor cells for various cytokeratins, glial fibrillary acidic protein (GFAP), S100 protein, alpha-smooth muscle actin (SMA), and vimentin were similar to those of pleomorphic adenoma of the parotid gland. The tumors examined in this study had different histological components, such as predominance of myxoid area, solid area, or tubuloductal structure, but immunoreactivity of both epithelial and myoepithelial tumor cells were the same in the tumors. Therefore, immunoreactivity of the tumor cells were the same among the intranasal pleomorphic adenoma having various histological components.

Actins↗
PubMed2000

Pleomorphic adenoma and adenolymphoma in ultrasonography.

OBJECTIVE: The aim of the study was to define ultrasonographic morphologic features characteristic of pleomorphic adenoma and adenolymphoma (Warthin's tumor). METHODS: Documentation of 31 ultrasonographic examinations of 20 pleomorphic adenomas and 10 Warthin's tumors in 28 patients was analysed. All cases were confirmed by fine needle aspiration biopsy or/and histopathological examination. Estimated ultrasound criteria were: borders (well-defined, predominantly well-defined, ill-defined), shape (lobulated, oval, irregular), echogenicity (increased, decreased), structure (homogeneous, slightly inhomogeneous, inhomogeneous) and presence of irregular anechoic areas within a tumor. RESULTS: 100% of the lesions were hypoechoic. 80.6% of all tumors were well-defined. The remaining 19.4% had predominantly well-defined borders. 55% of pleomorphic adenomas had a lobulated shape. Almost equal percentages of Warthin's tumors were lobulated, had an oval and irregular shape. Irregular echolucent areas were present in six of 11 examinations of Warthin's tumors and in one pleomorphic adenoma. CONCLUSIONS: Ultrasonography is a useful method for the evaluation of pleomorphic adenomas and Warthin's tumors and sometimes it might allow to suggest the nature of a tumor if a certain sonographic pattern is present.

Adenolymphoma↗
PubMed2000

Are myoepithelial cells responsible for the widespread expression of inducible nitric oxide synthase in pleomorphic adenoma? An immunohistochemical study.

Many of the actions of nitric oxide (NO) are still poorly understood. Recently, it has been shown that the inducible isoform of the enzyme nitric oxide synthase, iNOS, is expressed in both salivary ducts and pleomorphic adenoma. The current immunohistochemistry study determined whether or not this distribution correlated with smooth muscle actin (SMA) expression, thereby suggesting the expression by myoepithelial cells in both sites. Twenty cases of histologically confirmed pleomorphic adenoma, the sections of which contained adjacent normal salivary gland tissue, were stained for iNOS and smooth muscle actin (clone 1A4). The salivary ducts of all cases were stained intensely by both antibodies, with smooth muscle actin staining also being noted around acini in the normal gland parenchyma. Moderate or heavy staining for iNOS was found in all specimens of pleomorphic adenoma, with smooth muscle actin being distributed in a similar manner in 19 cases. Smooth muscle actin, but not iNOS, was also noted in blood vessels of both normal glands and tumours. The correlation between iNOS and SMA in pleomorphic adenoma was significant (P<0.001). The presence of iNOS in normal salivary ducts and pleomorphic adenoma is most likely due to expression by myoepithelial cells.

Actins↗
PubMed2003

Marginally excised parotid pleomorphic salivary adenomas: risk factors for recurrence and management. A 12.5-year mean follow-up study of histologically marginal excisions.

The aim of the study was to identify recurrence risk factors in surgically excised parotid pleomorphic salivary adenomas. We reviewed the case histories and histological findings for all cases of marginal or inadequate excision of pleomorphic salivary adenomas at the Royal Hallamshire Hospital, Sheffield, UK, between 1980 and 1995. A total of 83 cases with complete records were identified, with a mean follow-up period of 12.5 years. The histological slides were reviewed in each case. The overall recurrence rate was 6.0%. Where tumour was present at the margin, recurrence occurred in 17.6% of cases. However, cases conventionally regarded as marginally excised and likely to recur (tissue margin < 1 mm) showed recurrence in only 1.8% of cases. Intraoperative capsular rupture, microscopic capsular invasion by tumour and several other surgical factors were not predictive of recurrence. Adequate excision of pleomorphic salivary adenomas, in the sense of minimal recurrence risk, does not require more than a fraction of a millimetre of surrounding tissue. Only pleomorphic salivary adenomas with tumour actually at the excision margin require prolonged follow-up or consideration of radiotherapy. Provided that the tumour can be removed intact, the surgical approach for pleomorphic salivary adenomas should be guided by the need to preserve vital structures rather than by an attempt to remove a cuff of normal tissue with the tumour.

Adenoma, Pleomorphic↗
PubMed1999

Unusual presentations of pleomorphic adenoma and adenoid cystic carcinoma of the lacrimal gland.

PURPOSE: To report two atypical cases of pleomorphic adenoma and adenoid cystic tumours of the lacrimal gland. METHODS: Two case reports are presented. The first is of a 65-year-old female with a long history of right hypoglobus with sudden recent worsening. Computed tomography (CT) showed a round, well-defined lesion in the fossa for the lacrimal gland with an anterior hypodense extension suggestive of possible malignancy in a pleomorphic adenoma. The tumour in the second case, a 35-year-old male, was diagnosed after presentation following a relatively minor periorbital injury. The smooth rounded mass on CT scan was suggestive of a benign lacrimal gland tumour. RESULTS: The lesion in case 1 was excised with a diagnosis of haemorrhage within a pleomorphic adenoma. The lesion in case 2 was excised with a diagnosis of adenoid cystic carcinoma of the lacrimal gland with pseudocapsule. CONCLUSIONS: Haemorrhagic cyst developing beneath the pseudocapsule of a pleomorphic adenoma should be considered in the differential diagnosis of secondary development of malignancy in a pleomorphic adenoma. Adenoid cystic tumours of the lacrimal gland can present with a pseudocapsule.

Adenoma, Pleomorphic↗
PubMed2004

Pleomorphic adenoma of the lateral side of the tongue.

Pleomorphic adenoma is histopathologically the commonest tumor found in the major salivary glands. Pleomorphic adenoma originating from the tongue is very rare: only 26 cases have been reported in the world literature since 1960, only 2 of which originated from Ebner's gland. Herein we report the case of a 54-year-old female with pleomorphic adenoma of the tongue. The tumor was in contact with the molars. A partial glossectomy was performed with a surgical margin, as the preoperative pathological finding in the tissue specimen taken from the tumor was epithelial hyperplasia. The postoperative pathological diagnosis was pleomorphic adenoma with hyperplasia. It is unclear whether the teeth being in contact with the tumor caused tumorigenesis in this case. This case suggests that pleomorphic adenoma of the tongue originating from Ebner's gland should be considered in the differential diagnosis of lesions of the tongue.

Adenoma, Pleomorphic↗
PubMed2004

Pleomorphic adenoma of the palate.

Pleomorphic adenoma, is the most common tumor (50%) of the major and minor salivary glands. Seventy percent of the tumors of the minor salivary glands are pleomorphic adenomas, and the most common intraoral site is the palate, followed by the upper lip and buccal mucosa. Pleomorphic adenoma appears as a painless firm mass and, in most cases, does not cause ulceration of the overlying mucosa. Generally it is mobile, except when it occurs in the hard palate. Intraoral mixed tumors, especially those noted within the palate, lack a well-defined capsule. Lesions of the palate frequently involve periosteum or bone. Approximately 25% of benign mixed tumors undergo malignant transformation. Treatment for the pleomorphic adenoma is radical surgery. Inadequate resection leads to local recurrence. The authors report a palate pleomorphic adenoma in a 67-year-old female patient.

Adenoma, Pleomorphic↗
PubMedDate not supplied

Inter- and intratumoral variability in magnetic resonance imaging of pleomorphic adenoma: an attempt to interpret the variable magnetic resonance findings.

OBJECTIVES: The purpose of our study was to describe the various magnetic resonance (MR) findings of pleomorphic adenoma and to interpret these findings. METHODS: MR studies of 33 pleomorphic adenomas and 13 malignant tumors in the major salivary glands were reviewed. RESULTS: High signal intensity on short-inversion-time inversion recovery (STIR) and T2-weighted (T2W) images, progressive enhancement on dynamic MR images, and high apparent diffusion coefficient (ADC) values on diffusion-weighted (DW) images reflected myxoid-dominant components in pleomorphic adenomas. Hypercellularity with less-myxoid stroma showed reduced signal intensity on STIR and T2W images and also reduced ADC values on DW images, and the peak of time versus signal intensity curves (TICs) was reached earlier on dynamic MR images. CONCLUSIONS: The MR images of hypercellularity components in pleomorphic adenoma overlap with those of malignant parotid tumors. Detecting myxoid components by STIR, T2W, DW, and dynamic MR images is useful for predicting whether salivary gland tumors are pleomorphic adenoma or not.

Adenoma, Pleomorphic↗
PubMed2005

Carcinoma ex benign pleomorphic adenoma of the parotid gland.

BACKGROUND: Carcinoma in pleomorphic salivary adenoma is a common histologic subtype of primary parotid malignancy. METHODS: In this study, 28 patients (predominantly male) with histologically diagnosed carcinoma in pleomorphic salivary adenoma presenting over 10 years were retrospectively reviewed. RESULTS: Only 25 percent of patients had a previously treated pleomorphic salivary adenoma. Although the presenting features suggested malignancy in some cases, overall they were nonspecific, overlapping with the presentation of benign disease. Preoperative investigations included fine needle aspiration cytology, which was only 29-percent sensitive, and computed tomography and/or magnetic resonance imaging. There were 14 superficial and 12 total or radical parotidectomies. The facial nerve was resected en bloc with the tumor in nine cases and immediately reconstructed with good reanimation results in patients with recent-onset facial paresis. Only 44 percent of patients had a complete histologic tumor clearance, and this was the most significant determinant of survival (p < 0.01, log-rank analysis). The locoregional control rate was 66 percent at 5 years, but recurrent disease proved invariably fatal. Five-year disease-specific survival was 44 percent with a high rate of disease-specific mortality (87 percent). CONCLUSIONS: Carcinoma in pleomorphic salivary adenoma is very difficult to diagnose preoperatively. Fine needle aspiration cytology had a disappointingly low sensitivity for this tumor, potentially misdirecting surgical management. While good locoregional disease control could be achieved with surgery and radiotherapy, carcinoma in pleomorphic salivary adenoma was shown to be aggressive with a high disease-specific rate of mortality. Given that incomplete tumor resection was the most important prognostic factor, a high index of clinical suspicion, radical ablative surgery, and immediate soft-tissue and nerve reconstruction for proven cases are advocated.

Adenoma, Pleomorphic↗