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At least 19 recordsLinked to original sources
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↗
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↗
PubMed2026

Leptomeningeal Dissemination in TERT Promoter-mutant Anaplastic Pleomorphic Xanthoastrocytoma Responding to BRAF-MEK Inhibition: A Case Report.

Pleomorphic xanthoastrocytoma is a rare brain tumor that frequently harbors the oncogenic BRAF V600E mutation. Approximately 28.6%-47% of high-grade pleomorphic xanthoastrocytomas are associated with TERT promoter mutation and leptomeningeal dissemination, for which no established treatment exists and the prognosis remains poor. Combination therapy with BRAF and MEK inhibitors has demonstrated efficacy in BRAF V600E-mutant brain tumors. We report a case of a 22-year-old man with a right temporal lobe tumor initially diagnosed as World Health Organization grade 2 pleomorphic xanthoastrocytoma after gross total resection. Two years later, the tumor recurred and underwent malignant transformation to World Health Organization grade 3 pleomorphic xanthoastrocytoma. At the third resection, pathological and genomic analyses confirmed BRAF V600E mutation together with TERT promoter mutation. Following chemoradiotherapy, spinal leptomeningeal dissemination developed. After spinal irradiation, dabrafenib plus trametinib was initiated, resulting in partial radiological response and symptomatic improvement. Although regrowth occurred 10 months after initiation of targeted therapy, the patient remains alive at the time of writing. Here, we report a case of recurrent anaplastic BRAF V600E-mutant pleomorphic xanthoastrocytoma with leptomeningeal dissemination that showed a transient but clinically meaningful response to combined BRAF-MEK inhibition and spinal radiation therapy. In addition, this case raises the possibility of an association between TERT promoter mutation and leptomeningeal dissemination, although further studies are required to clarify this relationship.

BRAF V600E↗
PubMed1977

Pleomorphic carcinoma of the pancreas: an analysis of 15 cases.

Pleomorphic carcinoma of the pancreas is a well defined histopathological entity characterized by non-cohesive, sarcoma-like growth pattern, and bizarre mono- and multinucleated tumor giant cells with abundant eosinophilic cytoplasm. Fifteen cases are identified in autopsy files of the Department of Pathology, Washington University School of Medicine, which represent 7.1% of all the non-endocrine pancreatic malignancies found at autopsy. Pleomorphic carcinoma is comparable to pancreatic adenocarcinoma in clinical features such as age, sex, and presenting symptoms except that it is more likely to occur in the body and tail of the pancreas, metastases invariably develop, hematogenous spread is more common, and the median survival is worse. Pleomorphic carcinoma could be distinguished from the pancreatic tumors that resemble giant cell tumor of the bone. Differential diagnostic features between it and amelanotic melanoma, hepatocellular carcinoma, choriocarcinoma, pleomorphic liposarcoma, pleomorphic rhabdomyosarcoma, fibroxanthosarcoma, poorly differentiated epidermoid carcinoma, and giant cell carcinomas of the lung and thyroid are discussed.

Adenocarcinoma↗
PubMed1978

Ultrastructural observations in pleomorphic liposarcoma.

An ultrastructural study of pleomorphic liposarcoma with an unusual clinical presentation is described. A 69-year-old Caucasian female presented with recurrent superficial phlebitis of left leg, which responded only partially to conventional therapy. Following investigations, a mass was excised. Diagnosis of pleomorphic liposarcoma was made on microscopic examination. Numerous lipid droplets in the cytoplasm and often within intranuclear extensions of cytoplasm were seen on oil red O stain of frozen sections. Ultrastructural features are quite distinctive. The cells varied from small to often large pleomorphic cells with numerous lipid spaces without limiting membrane, large pleomorphic nuclei, and an abundance of cytoplasmic organelles. Centrioles were very prominent, in close proximity to nuclei, and collections of autophagocytic inclusions. Intercellular collagen was immature and scant. These features are compared to ultrastructural features of malignant fibrous histiocytoma, pleomorphic rhabdomyosarcoma, and cardiac myxoma, indicating that ultrastructural features are distinctive and help differentiate similar soft tissue tumors.

Aged↗
PubMed1975

Characterization of an antibody directed against a surface component of normal and pleomorphic cells of Streptococcus sanguis.

Whole cells of Streptococcus sanguis were utilized as an immunoadsorbent to purify large quantities of an antibody (S1) directed against a cell surface component. The S-1 antibody was isolated from antisera to normal (N) and pleomorphic (O) cells by a similar adsorption-elution procedure. The S-1 antibody isolated from antisera to N cells reacted in gel diffusion in identify with the S-1 antibody to O cells, indicating that the antigen which binds S-1 antibody (Ag-1) may not be radically altered when cells become pleomorphic. The S-1 antibodies directed against both N and O cells had restricted heterogeneity, indicating that for both types of cell Ag-1 may have a simple repeating structure. However, N cells were agglutinated to a greater extent by S-1 antibody than O cells. In addition the distribution of the bound S-1 antibody became altered as the cells became pleomorphic. Utilizing the technique of indirect immunofluorescence we observed that the S-1 antibody was distributed evenly on the surface of N cells. As the cells became pleomorphic, the antibody appeared to bind preferentially at the cell poles (capping). Later, as the cells became more grossly deformed, additional bands of immunofluorescence appeared to bisect the cells. Electron microscopic analysis indicated that the bound antibody was not associated with septal notches. The results suggest that the arrangement rather than the immunological properties of Ag-1 became altered as cells became pleomorphic.

Agglutination↗
PubMed1977

[Hematogenous metastases of benign pleomorphic adenomas of the salivary glands (author's transl)].

Hematogenous metastases of benign pleomorphic adenomas are exceptionally rare. In three secure reports of the world literature metastases occurred in lung, liver or bone after operation of a benign pleomorphic adenoma with the greatest interval of twenty-two years between operation and metastases. This will be interpreted as implantation-metastases. All other observations represented secondary carcinomas in pre-existing pleomorphic adenomas. The morphological criterias of an accurate classification are explained. A number of reports of the literature about metastases of benign pleomorphic adenomas deals with misinterpretations of secondary adenomas in pre-existing pleomorphic adenomas.

Adenoma↗
PubMed1975

Pleomorphous macrocellular pulmonary carcinomas. An anatomoclinical study on 193 cases.

A pathomorphologic study was carried out by the conventional histologic methods in 193 cases of pleomorphous macrocellular pulmonary carcinoma, of a total of 1,637 cases of lung cancer diagnosed histologically between January 1, 1961 and December 31, 1974. In comparison to other histologic types, the incidence of macrocellular carcinomas was of 11.8%, 62.6% belonged to the 40-60 years age-group, with male predominance. The results showed this carcinoma to be an autonomous type of neoplastic proliferation. The pathomorphologic particularities observed in the 193 cases and their evolution are conclusive arguments for considering pleomorphous macrocellular carcinomas as a separate histologic type in the classification of lung cancers. The term of pleomorphous macrocellular carcinoma appears to be the most comprehensive and in keeping with the histologic structure of these tumours. Cellular pleomorphism is an important diagnostic feature. Zones of specific differentiation observed in some cases may be included in the pleomorphism of these carcinomas. Notions of histogenesis are likewise discussed. It is increasingly assumed that these carcinomas are morphologically the expression of a cellular proliferation, differentiation and maturization response to the action of complex factors. The reduced stroma of these carcinomas indicate a more rapid increase of the tumoural parenchyma.

Carcinoma, Small Cell↗
PubMed2026

Pleomorphic Liposarcoma: Comprehensive Genomic Analysis of 39 Cases With Comparison to Other Genomically Complex Sarcomas.

Pleomorphic liposarcoma (PLPS) is an aggressive high-grade sarcoma that often shows diverse morphological features and can mimic high-grade undifferentiated pleomorphic sarcoma (UPS)/spindle cell sarcoma or myxofibrosarcoma (MFS), especially when pleomorphic lipoblasts are sparse. The molecular profile of PLPS is distinct from well differentiated/dedifferentiated liposarcoma and myxoid liposarcoma. In this study, we investigate 39 cases of PLPS by comprehensive genomic profiling, occurring in 32 patients with available molecular data. Cases were reviewed and morphologic parameters-lipoblastic component, UPS-like, and MFS-like areas were estimated. The genomic findings were collected and compared to UPS and MFS groups studied using the same platform. The cohort included 15 females and 17 males, with a median age of 56.5 (range, 34-78). The lower extremity (n = 17) was the most common site involved, followed by upper extremity (n = 5) and pelvis (n = 5). UPS-like and MFS-like patterns were the most common morphologic variants, ranging from 15% to 95% and 20% to 90%, respectively. TP53 (87%) and RB1 (51%) mutations and copy number alterations were the most common alterations seen, followed by ATRX (36%). Compared to UPS and MFS, TP53 and RB1 gene alterations were significantly more common in PLPS. Conversely, CDKN2A/B deletions were infrequent in PLPS. Survival analysis showed that MYC amplification was associated with significantly shorter overall survival in PLPS. Among histologic variants, CYSLTR2 alterations were found to be highest in cases with predominantly pleomorphic lipoblasts; additionally, strong correlations were found between gene alteration frequencies of MFS and MFS-like PLPS, and between UPS and UPS-like PLPS. RB1 allele-specific copy number analysis showed loss of heterozygosity in 82% of cases. Our cohort of PLPS showed a complex molecular landscape with distinct genetic alterations, histologic correlations, and clinical outcomes, highlighting its unique position among genomically complex sarcomas and providing insights that may inform future diagnostic and therapeutic approaches.

Humans↗
PubMed1978

[Ultrastructure and clinicopathology of pleomorphic adenomas of the salivary gland. I. Methods and results].

The observations are a ultrastructural analysis of pleomorphic adenomas with one's own 14 cases. Pleomorphic adenoma is chief representative of the secretory tumour complex of salivary glands. Ultrastructure of three dominate secretory tumor cells and three nonsecretory celltypes are descripted. Ultramicroscopical differentiation of stroma elements an their transformations, henceforth regressive of tumour cells in the pleomorphic adenoma are discussed. The author give instructions for electromicroscopic diagnostic of this adenomas. Lastly there is tried to determine the "dignity" of pleomorphic adenomas by their ultrastructure for purpose of a adequate therapy.

Adenoma↗
PubMed2026

Spindle Cell Predominant Anaplastic Pleomorphic Xanthoastrocytoma (WHO Grade 3) With Focal Piloid Features: A Rare Case Study With Comprehensive Molecular Profiling.

Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic tumor of the central nervous system. The typical form demonstrates relatively low-grade histologic features, whereas an anaplastic variant shows more aggressive behavior, including increased mitotic activity and necrotic changes. These tumors are often associated with alterations involving key growth signaling pathways and cell cycle regulatory genes, with molecular features that may resemble those seen in other high-grade astrocytic neoplasms. We describe an unusual example of an anaplastic pleomorphic xanthoastrocytoma showing focal piloid differentiation. The patient presented with acute neurologic symptoms, and imaging demonstrated a large, enhancing, well-circumscribed cerebral lesion with limited surrounding edema. Histologic evaluation revealed a highly cellular astrocytic neoplasm composed of spindle-shaped cells with marked pleomorphism, including scattered multinucleated forms, brisk mitotic activity, and necrotic areas. At the periphery, regions with elongated bipolar glial cells and occasional cytoplasmic inclusions suggestive of piloid morphology were identified. Molecular analysis demonstrated an activating alteration in the mitogen-activated protein kinase (MAPK) pathway along with additional genomic abnormalities, while mutations commonly associated with diffuse gliomas were not detected. The presence of piloid features within an otherwise anaplastic tumor is rare and may be relevant to the relatively favorable outcome observed during extended follow-up.

anaplastic↗
PubMed1977

Pleomorphic adenoma of the epiglottis: report of a case.

We describe the clinical and pathologic aspects of an unusual case of pleomorphic adenoma of the epiglottis. A 69-year-old man had impaired speech and a "lumpy sensation" in the throat. Following clinical evaluation and a diagnostic biopsy, the tumor was totally excised with excellent results. Pleomorphic adenoma of the larynx is most uncommon. To our knowledge, no report describing the clinical and pathologic features of this entity in the epiglottis or larynx has been previously reported. This is the only example of an epiglottic pleomorphic adenoma among 391 cases seen at Presbyterian-University Hospital and the Eye and Ear Hospital of Pittsburgh during a 21-year period.

Adenoma↗
PubMed1975

Hidradenomata of the external auditory meatus. (Review of the literature and report of a pleomorphic adenoma).

A case of hidradenoma of the external auditory meatus ('ceruminoma') is presented, with a review of the literature. The tumour has the appearances of a pleomorphic adenoma and is devoid of a capsule. It is suggested that the term hidradenoma be used for tumours of the ceruminous glands and that they be classified histologically as (1) adenoma, (2) pleomorphic adenoma, (3) adenoid cystic carcinoma and (4) adenocarcinoma. This classification aids treatment and prognosis. Attention is drawn to the high incidence of malignancy in hidradenomata of the external auditory meatus. The treatment of choice for pleomorphic adenomata is wide surgical excision with an adequate margin of normal skin. If there is doubt regarding complete removal, or a recurrence develops, a wider surgical excision is necessitated.

Adenoma, Sweat Gland↗
PubMed1976

Pleomorphic rhabdomyosarcoma of the larynx. A case report and review of the literature.

A case of pleomorphic rhabdomyosarcoma of the larynx occurring in a 33-year-old male is reported. The clinical and histopathological aspects of this undoubtedly rare neoplasm are described. After a quick review of the most important classifications of rhabdomyosarcoma so far made, the authors suggest a division into two basic groups, i.e. pleomorphic and fetal rhabdomyosarcoma, while the botryoid sarcoma and the alveolar rhabdomyosarcoma should be considered only as two subgroups of fetal rhabdomyosarcoma. From a comprehensive review of world literature on the subject, the well-documented cases up to now described are only seven, including the authors. The present case is the third one after the instances of pleomorphic rhabdomyosarcoma reported by Filipo and Crifo (1964 and by Rodriquez and Ziskind (1970).

Adult↗
PubMed1978

Glycosaminoglycan-synthetic activity of pleomorphic adenoma. Adenoid cystic carcinoma and nonneoplastic tubuloacinar cells of the salivary gland.

An analysis was carried out on glycosaminoglycan produced in pleomorphic adenoma, adenoid cystic carcinoma, sialadenitis and normal tissue of the salivary gland. After incubation of the tissue segments in a medium containing 35SO4, a radioautograph of the tissue section was made to observe the localization of 35SO4 incorporation, and 35S-labelled materials were purified from the tissues, and analyzed. High 35S-radioactivity was observed in the ductal cells of the inflammatory gland tissue and in the acinar cells of normal palatinal gland, but little radioactivity was observed in the interstitial components in these tissues, and the amount of 35SO4 incorporated in the tumor cells was also significant. Eighty to 90% of the 35S-radioactivity incorporated could be detected as 35S-glycosaminoglycans in all tissues except for the normal palatinal gland, which contained a large amount of 35S-sulfated glycoprotein. No significant difference in the synthetic activity of 35S-glycosaminoglycans and in their components were observed between nonneoplastic and neoplastic cells. These results suggest that glycosaminoglycan-producing cells in pleomorphic adenoma as well as in adenoid cystic carcinoma are derived from the tubuloacinar cells of the salivary gland.

Adenoma, Pleomorphic↗
PubMed2026

PDGFRA amplification could be a poor prognostic factor of advanced undifferentiated pleomorphic sarcoma in a comprehensive genomic profiling cohort.

BACKGROUND: Undifferentiated pleomorphic sarcoma (UPS) is the most common pleomorphic sarcoma, and its genomic landscape has been analysed, albeit in small numbers. This study aimed to clarify the relationship between gene variants and the prognosis of patients with advanced UPS. METHODS: This retrospective cohort study was conducted to analyse the data of patients with advanced UPS using a registry of the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) database up to Oct 2025 in Japan, analysed using comprehensive genomic profiling assay. RESULTS: A total of 233 patients with advanced UPS were identified in the C-CAT database; 151 men (64.8%), median age: 60.2&#xa0;years. TP53 variant (55%) was the most frequent event and the rate of Platelet-derived growth factor receptor alpha (PDGFRA) and KDR amplification were 9% and 6%, respectively. PDGFRA amplification co-occurred with KDR amplification (P&#xa0;<&#xa0;0.001). Survival from the initiation of chemotherapy was analysed by adjusting for length bias inherent in the database using the Kaplan-Meier estimator, an established method of adjustment. Patients with PDGFRA amplification (11 patients) had a worse prognosis than those without PDGFRA amplification [hazard ratio 2.9, 95% confidence interval 1.2-6.9 (P&#xa0;=&#xa0;0.02)]. TP53 alterations (P&#xa0;=&#xa0;0.24) were not associated with prognosis. In addition, treatment time with pazopanib with PDGFRA amplification [4 patients, 2.3&#xa0;months (1.2-11.2&#xa0;months)] was not different with those without PDGFRA amplification [28 patients, 3.8&#xa0;months (0.9&#xa0;months-not reached)] (P&#xa0;=&#xa0;0.52). CONCLUSIONS: For patients with advanced UPS, PDGFRA amplification was a poor prognostic factor and is not related to the efficacy of pazopanib treatment.

PDGFRA amplification↗
PubMedDate not supplied

Benign pleomorphic adenoma of the larynx. A case report.

Minor salivary gland tumors of the larynx are relatively rare. Morphologically the majority of them are adenoid cystic carcinomas and the overwhelming location is the subglottic larynx. Benign pleomorphic adenomas are rare minor salivary gland tumors of the larynx which usually occur at the glottic and subglottic levels. We present only the sixth case of a supraglottic benign pleomorphic adenoma that we could find in the literature. A preoperative laryngogram localized the tumor to the supraglottic larynx and the intact mucosa suggested a specific differential diagnosis. The tumor was removed by a lateral pharyngotomy with retention of good laryngeal function. The relatively asymptomatic presentation of our case is a somewhat unusual finding which, however, was previously noted in similar case reports.

Adenoma, Pleomorphic↗