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At least 19 recordsLinked to original sources
PubMed1990

[A rare case of pleomorphic adenoma of lateral wall of nasal cavity--with special reference of statistical observation of pleomorphic adenoma of nasal cavity in Japan].

Pleomorphic adenoma, which is also called mixed tumor is considered to occur favorably in major salivary glands such as parotid and submandibular glands, and rarely in the nasal cavity, pharynx, larynx, trachea, and lacrimal gland. We reported here a rare case of pleomorphic adenoma (2.9 X 2.2 X 1.7 cm3) developed from the lateral wall of right nasal cavity in a 43-year-old woman. Statistical observation of pleomorphic adenoma of the nasal cavity in Japan was made and comparative study was also made between such adenoma and that in the parotid gland. In Japan, 41 cases of pleomorphic adenoma originated in the nasal cavity have been reported so far including ours. These cases had age of onset of 16-74 years, averaging 44.6 years. Sex ratio showed female predominance. No significant difference was noted in affected sides sites. Chief complaints were represented mostly by nasal obstruction (29 cases; 71%) and nasal bleeding (23 cases; 56%). Tumors were surgically extirpated in all cases. One recurrent case (2.4%) was reported and another malignant case (2.4%) was also reported. 4 cases (9.8%) were originated in the lateral wall of nasal cavity and all of the other cases were in the nasal septum. In comparison with pleomorphic adenoma developed in parotid gland in Japan, sex ratio was 1:1.8 compared with 1:2.1 for parotid gland with almost similar tendency. Age of onset averaged 44.6 compare with 32.8 years for parotid gland, with a little advance in age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma, Pleomorphic↗
PubMed1992

Pleomorphic malignant fibrous histiocytoma: fact or fiction? A critical reappraisal based on 159 tumors diagnosed as pleomorphic sarcoma.

Pleomorphic malignant fibrous histiocytoma (MFH) is regarded as the most common soft tissue sarcoma of adulthood, but no definable criteria exist for its diagnosis. Possibly its only distinctive feature is its apparent lack of specific differentiation. To determine the validity of pleomorphic MFH, 159 tumors diagnosed as pleomorphic sarcomas have been reassessed morphologically, immunohistochemically, and ultrastructurally, where possible. Of these 97 cases (63%) proved to be specific sarcomas other than MFH, 20 proved to be nonmesenchymal neoplasms, and 42 were unclassifiable (of which 21 were either small biopsies or subtotally necrotic). Only 13% of these cases were eligible for consideration as MFH, but these showed no reproducible histological differences from the other tumors studied, nor was this group morphologically consistent. These tumors showed no evidence of true monocyte/macrophage differentiation. It is postulated that pleomorphic MFH is a noncohesive heterogeneous group of poorly differentiated neoplasms, a term that has become a meaningless diagnosis of convenience. With sufficient effort, a specific line of differentiation can be identified in the majority of pleomorphic malignant soft tissue tumors; with advances in investigative technology, the proportion that remain unclassifiable is very likely to diminish further in the future.

Adolescent↗
PubMed1979

Malignant soft tissue tumors (malignant fibrous histiocytoma, pleomorphic liposarcoma, and pleomorphic rhabdomyosarcoma): an electron microscopic study.

A comparative ultrastructural analysis of malignant soft tissue tumors (malignant fibrous histiocytoma, pleomorphic liposarcoma, and pleomorphic rhabdomyosarcoma) revealed similar ultrastructural features in this group of tumors. However, by electron microscopy these tumors can be differentiated on the basis of cytoplasmic and extracytoplasmic features (myosin filaments, lipid droplets, and perinuclear intermediate filaments, for example). This is even true of less well differentiated tumors and tumor cells. These findings support and amplify the concept of a common histogenesis for tumors of mesenchymal origin. Paradoxical features observed by light microscopy warrant further study by electron microscopy if the correct diagnosis is to be made in atypical cases, such as apparent malignant fibrous histiocytoma with cross striations.

Adult↗
PubMed1992

Pleomorphic variant of invasive lobular carcinoma of the breast.

Infiltrating lobular carcinoma (ILC) of the classic type is well recognized; less well appreciated is a group of variant forms of ILC, which includes solid, alveolar, mixed, apocrine, signet-ring, histiocytoid, and tubulolobular variants. In addition, Page et al (Diagnostic Histopathology of the Breast, Churchill Livingstone, 1987, pp 219-226) recently have emphasized the pleomorphic variant of ILC, which demonstrates the infiltrating pattern of classic ILC; however, the nuclei are more pleomorphic and have features that may overlap with those of infiltrating duct carcinoma. To determine whether pleomorphic ILC shows significant prognostic differences from classic ILC, we reviewed the clinical courses of 25 patients with classic ILC and compared them with 16 patients with pleomorphic ILC. The major determinant in placing ILC into the pleomorphic category was the presence of nuclei of nuclear grade 2 or 3. All classic ILCs had nuclei of grade 1 by the Scarff-Bloom-Richardson criteria. Survival to recurrence was significantly worse (P less than or equal to .05) for the patients with pleomorphic ILC at lengths of survival greater than 30 months. In addition, node-negative patients with pleomorphic ILC were four times more likely to experience recurrence than node-negative patients with classic ILC; those with positive nodes and pleomorphic histology were 30 times more likely to experience recurrence. Although there appeared to be a trend toward decreased overall length of survival for those patients with pleomorphic ILC when compared with patients with classic ILC, this difference was not statistically significant.

Adult↗
PubMedDate not supplied

Measurement of DNA content and nuclear pleomorphism in metastatic variants of the B16 murine melanoma and hamster lymphoma and its liver metastasis using image analysis techniques.

The DNA content and nuclear pleomorphism (NPM), which are two cellular features consistently employed in the assessment of tumour malignancy, have been measured in B16 murine melanoma metastatic variants and in hamster primary lymphoma and its liver metastasis as tumour models using image analysis techniques. The three melanoma variants studied were the low metastasis variant F1, the BL6 variant selected for high lung metastasis and invasive ability, and ML8, a line isolated from pulmonary metastasis of the BL6 tumour. The cellularity of the melanomas bore no relationship to metastatic ability. The cell cycle distribution of nuclei based on integrated nuclear density (IND) was studied. The ML8 tumour showed higher DNA ploidy. Also, in this tumour the S-phase fraction was approximately 2.0-fold larger than that of the BL6 tumour. Flow cytometry of nuclei isolated from paraffin-embedded tumour tissue showed all three melanomas were aneuploid. In both F1 and BL6, two distinct subpopulations (p2 and p3) of nuclei, based on the degree of their pleomorphism, could be discerned. A significantly higher proportion of the more pleomorphic subpopulation (p2) occurred in BL6 than in F1. In the ML8 alone, a third subpopulation (p1), which was more pleomorphic than p2, was found. The hamster lymphomas (HALY-malignant and N-HALY-non-malignant) were less cellular than the metastatic tumour (HALY-met) in liver. The lymphomas N-HALY and HALY-met had a higher DNA ploidy as compared with its primary tumour HALY. However, the non-malignant lymphoma N-HALY and the moderately malignant hamster fibrosarcoma were also found to be hyperdiploid. The metastatic lymphoma (HALY-met) showed a more pleomorphic nuclear subpopulation as compared with the primary. No differences were found in the size of the S-phase fractions of the hamster tumours. The present work shows that image analysis techniques enable one to make objective measurements of DNA content and nuclear pleomorphism of tumour cells, and suggests that in the tumour models investigated there is increased nuclear pleomorphism and DNA ploidy associated with tumour progression.

Animals↗
PubMed1987

Pleomorphic rhabdomyosarcoma in adults: immunohistochemistry as a tool for its diagnosis.

Pleomorphic rhabdomyosarcoma in adults over 30 years of age was a diagnosis frequently made in the 1960s and 1970s. Since the general acceptance of malignant fibrous histiocytoma (MFH) as a tumor entity at the end of the 1970s, however, it has become a very rare tumor in adults. Therefore, 21 cases originally diagnosed on the basis of histology and clinical data as pleomorphic rhabdomyosarcoma in the 1960s and 1970s were reexamined immunohistochemically. Other types of pleomorphic sarcomas involved in the differential diagnosis were also studied. Specific antibodies against vimentin, desmin, creatine kinase subunit M, skeletal muscle actin and myosin, and myoglobin, and the avidin-biotin-peroxidase complex technique were used. The immunohistochemical findings indicate that rhabdomyosarcoma occurs only rarely in adults over 30 years of age and that the majority of the tumors have to be reclassified as MFH or leiomyosarcoma. On the other hand, several pleomorphic sarcomas were found to be diagnosed incorrectly as MFH or liposarcoma by routine histologic stains and electron microscopy. The revised diagnosis was pleomorphic rhabdomyosarcoma for one case and pleomorphic leiomyosarcoma for the other cases. Thus, this study clearly shows the usefulness of immunohistochemistry as a technique in the diagnosis of pleomorphic sarcomas in adults.

Adult↗
PubMed1972

Initiation of dermatophyte pleomorphic strain sporulation by increased aeration.

A normally asporogenous pleomorphic strain of Microsporum gypseum was induced to sporulate by controlled aeration and dehydration. Aeration of the pleomorphic strain under optimal cultivation conditions caused the initiation of a sporulation cycle with equivalent growth parameters and percentage intracellular water loss as the wild-type strain. Initiation of sporulation was not due to alteration of the medium's nutrient concentration or consistency, concentration of fungal growth by-products, or removal of volatile "staling factors." Macroconidia formed by the pleomorphic colonies were of characteristic wildtype morphology, but germinated to form typical pleomorphic colonies, indicating that the induced sporulation was strictly phenotypic and reversible. Other asporogenous pleomorphic strains from different dermatophyte genera also were induced to form macroconidia by aeration, suggesting a similarity in sporulation induction in Microsporum sp., Epidermophyton floccosum, and Trichophyton violaceum. Initiation of sporulation by aeration further suggested that the pleomorphic mutation was one which affected the sensitivity of the pleomorphic aerial hyphae to natural sporulation inducers (i.e., decreased humidity) and did not represent a loss in the ability to form fertile macroconidia.

Aerobiosis↗
PubMed1976

[A pathological classification of pleomorphic adenoma of the salivary glands (author's transl)].

Pleomorphic adenomas of the salivary glands show, despite their pleomorphism, certain histological characteristics. These are based onthe differentiation of the epithelial cell and the amount and nature of the stroma. A systematic histological analysis of 310 pleomorphic adenomas of the parotid gland resulted in the following findings and classification. 1. The most frequent epithelial cell forms were salivary duct and myoepithelial cells (75-90%) seen as epidermoid cell groups (75%). Rarer forms of differentiation were striated duct cells (5%), keratinised squamous epithelium (2,5%), oncocytes (1%), basal cells (1%), and sebaceous gland cells or goblet cells (less than 1%). 2. A myxomatous stroma represented the prototype of stromal differentiation (80%). A chondroid stroma was found in 10% of cases examined and a mixed mucochondroid stroma in 3%. Further differentiation included hyaline stroma (25%) and fibrous stroma (15%) especially in the older tumour or after irradiation. Rarely was a fascicular (0,5%) or osseous (1%) stromal change found. 3. Four subgroups of pleomorphic adenoma can be classified from consideration of the epithelial and stromal changes. Subgroup 1 (30,5%) is the classical pleomorphic adenoma with a stroma content of 30-50%; subgroup 2 (55%) has a stroma content of 80%; subgroup 3 (9%) has a poor stroma content of 20-30% or less and an epitaelial differentiation similar to subgroup 1; and subgroup 4 has also a poor stroma content (6%) with a relatively monomorphic epithelial structure. 4. Recurrences (13,5%) were seen more in stroma-rich pleomorphic adenomas than in stroma-poor tumours. 5. On the basis of cytological differentiation, pleomorphic adenomas develop from indifferent tissue adjacent to salivary intercalated or striated ducts.

Adenoma↗
PubMed1989

[A pleomorphic lipoma of the palm--comparison to spindle cell lipoma].

A pleomorphic lipoma usually occurs in the neck, the shoulder, and/or on the backs of men over the age of 50. This tumor displays a mixture of fat cells, pleomorphic cells, floret cells, and bundles of mature collagen fiber. Herein we report on a pleomorphic lipoma that occurred on the palm of a 56-year-old woman. An immunohistochemical study, performed to compare the characteristics of a pleomorphic lipoma with those of a spindle cell lipoma, has suggested that the pleomorphic and floret cells of a pleomorphic lipoma are similar to the spindle cells of a spindle cell lipoma and not to fat cells. Our result seems to indicate that these two tumors are on the same spectrum and only the quantity of the pleomorphism keeps them distinct.

Diagnosis, Differential↗
PubMed1992

Polyploidy in pleomorphic adenomas with cytological atypia.

Occasionally, in fine-needle aspirates of pleomorphic salivary gland adenomas, considerable cytonuclear atypia is present, which may give rise to a false-positive diagnosis. In this study DNA cytophotometry was performed on Feulgen restained smears prepared from material obtained by needle aspirates of normal salivary glands (n = 4), pleomorphic adenomas with (n = 5) and without (n = 4) atypia and a carcinoma in a pleomorphic adenoma. The results showed a clear diploid DNA histogram in the specimens of normal salivary gland and pleomorphic adenomas without atypia. In contrast, in the pleomorphic adenomas with atypia a distinct polyploid pattern was present in three out of the five DNA histograms with DNA values in 2c, 4c and 8c ranges. In two of these cases a 16c peak was also present and in the two remaining cases tetraploidy was demonstrated. In the carcinoma a main stemline at 4c was found. This report once more emphasizes the possible atypia which may be present in FNA of pleomorphic adenomas of the salivary gland. The atypia is due to polyploidy in a histologically benign tumour.

Adenoma, Pleomorphic↗
PubMed1991

Muscle-specific protein expression in normal salivary glands and pleomorphic adenomas: an immunocytochemical study with biochemical confirmation.

Normal salivary gland myoepithelia are contractile cells with hybrid epithelial/myogenic ultrastructural features. It is known that these cells co-express the intermediate filaments cytokeratin, vimentin, and occasionally GFAP. This complex cytoskeletal immunophenotype is also reflected in multiple morphologic cell types of pleomorphic adenoma. At present, the myofilament complement of normal and neoplastic myoepithelium is not well defined. We have evaluated the expression of desmin and smooth and sarcomeric muscle actins in 11 normal salivary glands (six snap-frozen and five methacarn fixed) and 26 pleomorphic adenomas (11 snap-frozen and 15 methacarn fixed) by ABC-immunoperoxidase method. Two of 11 frozen pleomorphic adenomas contained the muscle-specific intermediate filament desmin, which is not found in the normal glands. This novel finding was confirmed by gel electrophoresis and immunoblot. Using specific antibodies, normal gland myoepithelial cells consistently contained muscle actin isoforms of the smooth muscle type but not sarcomeric muscle actins. Muscle actin expression by the neoplastic cells of pleomorphic adenoma was found in 13 of 26 tumors (six of 11 frozen tumors (desmin negative) and seven of 15 methacarn fixed tumors). In comparison to the normal myoepithelial cell, the transformed myoepithelial-like cells of pleomorphic adenoma are not always characterized by a muscle actin cytoskeleton. Expression of desmin intermediate filaments in pleomorphic adenomas appears to be a rare event that is independent of a muscle actin cytoskeleton.

Actins↗
PubMed1988

Malignant pleomorphic adenoma (malignant mixed tumor) of the trachea. Report of a case.

Malignant pleomorphic adenoma arising in the trachea has not been reported in the literature. We report here a case of malignant pleomorphic adenoma (malignant mixed tumor) occurring in the trachea of a 65-year-old woman. The tumor metastasized to the lung and the chest wall 11 years after complete resection of the primary tumor, which was a polypoid submucosal tumor, 1.3 cm in diameter. Light microscopic examination of the primary and metastatic tumors showed the presence of epithelial and stromal elements, consisting of grandular structures, foci of squamous metaplasia and a myxochondroid stroma. Many tumor cells showed myoepithelial cell features by electron microscopy, and immunoreactivity for S-100 protein and GFAP was also seen in many of them. These findings were consistent with those of pleomorphic adenoma. However, the epithelial elements were cytologically atypical with prominent mitotic figures. Infiltration of the tumor cells into the surrounding soft tissue was also seen. No foci of benign pleomorphic adenoma were found in the primary tumor. These findings indicate that this tumor was not a carcinoma ex pleomorphic adenoma, but a true malignant pleomorphic adenoma (true malignant mixed tumor) of the trachea.

Aged↗
PubMed1991

Immunohistochemical study of pleomorphic adenoma of lacrimal gland.

Immunohistochemical examinations of lacrimal gland specimens were carried out with monoclonal antibodies to S-100 protein and glial fibrillary acidic protein (GFAP) in 3 cases of normal tissue, 2 cases of hypertrophy and 3 cases of pleomorphic adenoma of the lacrimal gland. In specimens of normal lacrimal gland tissue, S-100 protein was identified in myoepithelial cells and ductal epithelia, but GFAP was not identified in any part of the gland. In specimens of lacrimal gland hypertrophy, the findings were identical. In pleomorphic adenoma of the lacrimal gland, asteroid cells in the myxoid and/or chondroid areas were strongly stained by antibodies to both S-100 protein and GFAP. In the solid areas of pleomorphic adenoma specimens, S-100 protein-positive fusiform or round cells and GFAP-positive round cells were observed. It was thought that S-100 protein-positive cells could have originated from myoepithelial cells and that GFAP could be a tumor-associated antigen. These findings agreed with recent immunohistochemical findings in pleomorphic adenoma of the salivary gland. It was speculated that pleomorphic adenoma of the lacrimal gland could cause mesenchymal metaplasia of the myoepithelial cells, as happens in pleomorphic adenoma of the salivary gland.

Adult↗
PubMed1990

[Immunohistochemical study of pleomorphic adenoma of the lacrimal gland].

We performed immunohistochemical examinations in 1 hypertrophy and 3 pleomorphic adenomas of the lacrimal glands with monoclonal antibodies to S-100 protein and GFAP (glial fibrillary acidic protein). It was thought that hypertrophy of the lacrimal gland would be cytological equivalent to normal lacrimal gland tissue because of the lack of cytological atypia except when accompanied by lymphoid infiltration. In hypertrophy of lacrimal gland, S-100 protein was identified in myoepithelial cells and parts of the ductal epithelia, but GFAP was not identified in any part. In pleomorphic adenomas of lacrimal glands, asteroid cells of myxoid and/or chondroid areas were strongly stained with both antibodies to S-100 protein and GFAP. In solid areas of pleomorphic adenomas, S-100 protein-positive fusiform or round cells and GFAP-positive round cells were observed. It was thought that S-100 protein-positive cells could have originated from myoepithelial cells and GFAP could be a tumor-associated antigen. The results coincided with recent immunohistochemical findings of pleomorphic adenoma of the salivary gland. It was suspected that pleomorphic adenoma of lacrimal gland could develop from mesenchymal metaplasia of myoepithelial cells as in the case of pleomorphic adenoma of salivary gland.

Adult↗
PubMedDate not supplied

[Myxoid liposarcoma and pleomorphic liposarcoma: cyto-histological correlations].

Myxoid liposarcoma and pleomorphic liposarcoma: cito-histological correlations. A correlative cytologic and histologic study of a myxoid liposarcoma of the shoulder in a 72 year-old man and a pleomorphic liposarcoma observed in the retroperitoneum of a 84 year-old woman, are presented. A preoperative FNAB cytology performed in both cases showed necrotic material containing spindle-stellate shaped cells, interspersed in a myxoid matrix, with rare classical monovacuolated lipoblasts and fragments of plessiform vessels were seen in the first and scattered pleomorphic and multinucleated cells, with prominent nucleoli and numerous atypical mitosis in the second. A malignant mesenchimal spindle-cells tumor, with myxoid matrix and pleomorphic cells, consistent with liposarcoma, respectively were suspected. Gross and histological specimens confirmed the cytological suspect. Authors discuss main cyto-histological differential diagnoses of myxoid tumors, and point out the importance and a correct differentiation between myxoid liposarcoma and intramuscular myxoma. The cytologic appearance of pleomorphic liposarcoma is similar to histologic type and therefore the problem of a differential diagnosis with soft tissue tumors is analogous. When mono or plurivacuolated lipoblasts are absent, differential diagnosis between pleomorphic histiocytoma and liposarcoma is impossible. Nevertheless this is not a important problem at cytological level because both tumors have a had prognosis and must be treated with radical surgery. Definition of correct histologic type will be more suitable on histologic specimens.

Aged↗
PubMed1988

[Expression of epithelial and nervous-system-related antigens on pleomorphic adenoma of the salivary glands--an analysis of 20 cases].

The expression of cytokeratin (40-52 kD), carcinoembryonic antigen (CEA), vimentin, neuron-specific enolase (NSE), S-100 protein, glial fibrillary acidic protein (GFAP) were investigated in 20 cases of pleomorphic adenoma of the salivary glands and 10 cases of normal salivary glands, in order to analyze and correlate the antigens' expressions with the probably histogenetic mechanisms of the various histopathological differentiations in pleomorphic adenoma of the salivary glands and their probably original cells in normal salivary glands. Immunohistochemistry has provided some evidence for the relationship of the tumor cells to normal salivary glands: In the normal glands, the acinic cells exhibited cytokeratin, CEA and focal, predominantly nuclear S-100 protein staining. In both normal glands and pleomorphic adenomas, the duct-lining cells were immunoreactive for cytokeratin, CEA and had both cytoplasmic and nuclear S-100 positivity; The myoepithelial cells of the normal glands as well as the periduct cells, epithelial nests/cords, squamous metaplasia and the stellate/spindle/cartilaginous cells in the myxomatous-chondroid areas of the pleomorphic adenoma contain immunoreactive vimentin, NSE, S-100 proteins and GFAP, and lesser amounts cytokeratin (40-52 kD)/CEA. The varicosities of the terminal axon may lie directly on the basal membrane, or penetrate the basal membrane and lie in direct contact with the effector cells (duct-acinar-myoepithelial cells) of the salivary glands. The peripheral neurons and axons of the autonomic nervous system were identified by vimentin, NSE, S-100 proteins and GFAP. The combination of epithelial cytokeratin and nervous system-related vimentin, NSE, S-100 and GFAP immunostaining in myoepithelium of the normal glands and in all component elements (particularly the periduct cells) of pleomorphic adenoma reflects pleomorphic adenoma of the salivary glands is an epithelial tumor, the probably original cells or the probably histogenetic mechanisms of the various histopathological differentiations is correlated not only with "duct-acinar-myoepithelial cells" but also with the neuroectoderm in the normal salivary glands."

Adenoma↗
PubMedDate not supplied

Ultrastructural contributions to the study of morphological differentiation in malignant mixed (pleomorphic) tumors of salivary gland.

Ultrastructural studies of pleomorphic adenoma have shown a coordinated differentiation of luminal epithelial and modified myoepithelial cells with the latter cells related to processes resulting in the myxochondroid stroma. Five examples of various histologic types of malignant mixed tumor of parotid origin were examined by electron microscopy to see if underlying patterns of tumor cell differentiation and organization matched those of pleomorphic adenoma. Whether they were intracapsular tumors (with or without identifiable pleomorphic adenoma), carcinomas ex pleomorphic adenoma, or a true malignant mixed tumor, all lesions had cell types and organizations either identical to those in pleomorphic adenoma or, as in less-differentiated examples, displayed features suggesting origin from luminal cells, myoepithelial cells, or both. Even the chondroid cells in the true malignant mixed tumor expressed ultrastructural features indicating their epithelial derivation. On the basis of these findings, some alterations to the classification and terminology of the subtypes of malignant mixed tumor are suggested.

Adenoma, Pleomorphic↗
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↗