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PubMed2005

A case of pleomorphic xanthoastrocytoma presenting with massive tumoral hemorrhage.

Pleomorphic xanthoastrocytoma has been generally conceived to be in a benign nature, showing a relatively favorable prognosis. Apoplectic attack attributable by massive hemorrhage in this distinct form of the supratentorial glioma is an exceedingly rare event. A 61-year-old female presented with a sudden onset of generalized tonic--clonic convulsion. CT and MRI disclosed the presence of a tumor composing of massive intra-tumoral hemorrhage filling the cyst associated with mural nodule in the left frontotemporal lobe. At surgery, the subpial mass involving hematoma was well marginated and slightly adherent to the dura mater. It could be removed totally and proved to be a pleomorphic xanthoastrocytoma. The unusual hemorrhagic presentation of this typically benign entity is extremely rare and is thought to be intra-tumoral bleeding in this case, since subarachnoid hemorrhage was absent.

Astrocytoma↗
PubMed1976

Polypoid spindle-cell carcinoma (pleomorphic carcinoma). Report of a case occurring on tongue and review of the literature.

A case of spindle-cell carcinoma (pleomorphic carcinoma), a rare polypoid tumor of the tongue, is reported. The characteristic clinical, gross, and microscopic features of this peculiar lesion and its common sites of location are presented. Origin and pathogenesis of the sarcoma-like elements of the lesion are discussed and the literature on the subject is reviewed. Sites of apparent transition between the spindle cell elements of the tumor and the overlying epithelium were observed in light microscopic sections, and the electron micrographs of the spindle-cell portion of the lesion demonstrated the presence of tonofilaments and desmosomes in many tumor cells. These findings support the concept that this group of lesions are pleomorphic variants of squamous-cell carcinoma with predominantly spindle-cell pattern. Current evidence in the literature also suggests that metaplastic transformation of the tumor cells into mesenchymal elements may take place in some of these lesions, and that "metaplastic carcinoma" may probably be a more proper designation for them.

Aged↗
PubMed1980

Pleomorphism and the problem of recrudescent parasitaemia following treatment with salicylhydroxamic acid (SHAM) in African trypanosomiasis.

The curative action of a single dose of salicylhydroxamic acid (SHAM) in combination with glycerol was investigated in mice infected with a variety of monomorphic and pleomorphic African trypanosomes. The treatment of mice infected with monomorphic members of the sub-genus Trypanozoon was always successful and resulted in a complete cure. Treatment of animals with pleomorphic infections resulted in an initial clearance of the parasitaemia which later recrudesced. Both chronic and acute infections with Trypanosoma vivax were radically cured with SHAM plus glycerol, while infections with T. congolense and T. musculi were never cured.

Animals↗
PubMed1990

Giant cell tumor of the pancreas of mixed osteoclastic and pleomorphic cell type: evidence for a histogenetic relationship and mesenchymal differentiation.

We describe a giant cell tumor of the pancreas composed of a mixture of osteoclastic and pleomorphic cell types. This rare tumor had a unique immunohistochemical profile. Both types of tumor giant cells stained for vimentin, alpha-1-antitrypsin, alpha-1-antichymotrypsin, synaptophysin, muscle actin, and neuron-specific enolase, but not for epithelial markers. Electron microscopy showed cells which resembled primitive fibroblasts and osteoclast with no epithelial features. These findings are most consistent with mesenchymal differentiation. The extensive homologies in immunohistochemical staining of both osteoclastic and pleomorphic giant cells in this case indicates that these cells are histogenetically related.

Carcinoma↗
PubMed1991

The pleomorphic xanthoastrocytoma and its differential diagnosis: a study of five cases.

Five brain tumors with the histopathologic features of pleomorphic xanthoastrocytomas (PXAs) are presented. Computed tomography scans showed a remarkable homology. Two cases had atypical localizations for a PXA, while one 46-year-old patient did not conform to the normal age distribution of this tumor. Nevertheless, in these cases, the histopathology was always characteristic for PXA, a remarkable pleomorphism, in addition to simultaneous expression of glial fibrillary acidic protein and histiocytic markers in the various tumor cells. In one of the presented tumors, however, clusters of neoplastic neuronal cells were also found. In this particular case, differential diagnostic criteria to distinguish between a PXA and a desmoplastic infantile ganglioglioma are lacking.

Adolescent↗
PubMed1995

Pleomorphic xanthoastrocytoma with invasion of the tentorium and falx.

A case of a 21-year-old patient with a recurrent pleomorphic xanthoastrocytoma with invasion of the tentorium and falx cerebri is reported. Dural attachment has been reported in some cases. Invasion of the dura of the falx cerebri and complete infiltration of the left tentorium by the tumor were found intraoperatively. This is the first case in the literature which shows invasion of the dura in a pleomorphic xanthoastrocytoma.

Adult↗
PubMed2004

Epithelioid variant of pleomorphic liposarcoma: report of a case.

A case of an epithelioid variant of pleomorphic liposarcoma (PL) arising in the back of a 72-year old male is presented. The lesion was a well-circumscribed but unencapsulated, yellowish white mass measuring 11 x 10 x 9 cm in the subcutis and muscle. Histologically, the tumor consisted of three elements; an epithelioid cell element occupying about 50%, a lipogenic and mixed lipogenic and epithelioid cell element occupying 40%, and a malignant fibrous histiocytoma-like element. The lipogenic area was composed of uni- and multivacuolated pleomorphic lipoblasts. Immunohistochemically, the tumor was positive for vimentin, epithelial membrane antigen, and CD10. It was negative for desmin, alpha-smooth muscle actin, muscle actin, S-100 protein, and cytokeratins 8 and 18. The epithelioid variant of PL should be differentiated from metastatic renal cell carcinoma and adrenal cortical adenocarcinoma.

Aged↗
PubMed2005

Pleomorphism of the clinical manifestations of neurocysticercosis.

Neurocysticercosis (NCC) remains a major public health problem in developing countries as it is the most common helminthic infection of the central nervous system. Clinical manifestations are non-specific and pleomorphic. Case reports on uncommon presentations of NCC are few. We report six interesting cases of NCC with unusual clinical presentation that demonstrate this spectrum of pleomorphism. These include extrapyramidal disease (parkinsonism and focal dystonia), Kluver-Bucy syndrome, Weber's syndrome, dementia and cortical blindness. The clinical details and possible mechanisms for the uncommon presentations are also discussed. Thus, a high level of suspicion should be kept for NCC, especially in endemic zones and developing countries.

Adult↗
PubMed2006

[Myxoid pleomorphic fibroma of the skin].

Pleomorphic fibroma of the skin was described by Kamino et al 1 in 1989. It is a benign fibroblastic proliferation with cytologic atypia. This article describes a case of a myxoid variant of pleomorphic fibroma of the skin.

Fibroma↗
PubMed2004

Interleukin-6/soluble interleukin-6 receptor signaling attenuates proliferation and invasion, and induces morphological changes of a newly established pleomorphic malignant fibrous histiocytoma cell line.

Pleomorphic malignant fibrous histiocytoma (MFH) is occasionally associated with inflammatory paraneoplastic syndrome (PNS). Recently, we reported that interleukin (IL)-6, one of the candidate cytokines, which induces such systemic inflammatory reaction, may be a tumor-associated factor involved in the pathogenesis and its clinical manifestations of MFH. In the local microenvironment, tumor-induced inflammatory reaction may play a role favoring tumor progression. To clarify the biological relevance of IL-6 in MFH, we established a human MFH cell line, named MIPS-2, derived from a resected specimen of a patient presenting with PNS. In this patient, the serum IL-6 level ran parallel to the disease course: elevated serum IL-6 concentration normalized immediately after radical surgery, and re-elevation occurred on tumor recurrence. MIPS-2 presented pleomorphic appearance, severe nuclear abnormalities with prominent nucleoli, and tumorigenesis in nude mice. MIPS-2 expressed IL-6, IL-6 receptor (IL-6R), and glycoprotein 130 (gp130) but lacked the soluble form of IL-6R (sIL-6R), as determined by flow cytometry and reverse transcriptase-polymerase chain reaction analyses. Stimulation of MIPS-2 with IL-6 combined with exogenous sIL-6R induced phosphorylation of both signal transducer and activator of transcription 3 (STAT3) and mitogen-activated protein kinase (MAPK), decreased cell proliferation, attenuated invasion, and induced morphological changes. Collectively, these data suggested that the IL-6/sIL-6R signaling pathway plays a pivotal role for proliferation, invasion, and morphology of MFH via STAT3 and MAPK pathway as autocrine and/or paracrine manner, and proposed the therapeutic potential for the use of both anti-growth factor and proinflammatory cytokine-targeting strategies to combat devastating MFH.

Adult↗
PubMed1987

Pleomorphic adenoma of the cervical esophagus: a rare tumor.

Pleomorphic adenoma of the esophagus is a rare tumor: less than 10 cases have been reported. These pleomorphic neoplasms are sessile and arise in the submucosal glands of the esophagus. Described in this report is the long-term follow-up of an additional case, in which the resection was reinforced with a pectoralis major muscle wrap.

Adenoma↗
PubMed2004

[Pleomorphic xanthoastrocytoma. A review of five observations].

BACKGROUND AND PURPOSE: We present a review of five patients who developed pleomorphic xanthoastrocytomas, presenting the clinical features, pathology findings and therapeutic approach of these rare tumours which almost always occur in children and young adults. METHODS: This paper is a retrospective study of five patients (three males and two females), treated from 1985 to 1996. RESULTS: Seizure was the most frequent symptom. The tumor was located in the temporal or temporo-parietal lobe in two patients, in the parietal lobe in one, the frontal in one and in hypothalamus and third ventricle in the final patient. To our knowledge, no case of pleomorphic xanthoastrocytoma located in the area of hypothalamus/third ventricle has been reported in the literature. All patients underwent surgery which was complete for two patients, subtotal for two others and partial for one. Four were given post-operative cerebral radiation therapy (two recurrences and malignant transformation and two erroneous diagnoses) (mean dose: 44.75 Gy), for two patients surgery was followed by chemotherapy. One patient was lost for follow-up. Two patients presented at least one tumor recurrence. Two died from malignant transformation. Two patients are alive without recurrence at 12 and 16 years from diagnosis with excellent quality-of-life (Glasgow Outcome Scale=I). CONCLUSION: Surgery is the gold standard treatment. Prognosis is very good (except for malignant transformation), so that a close long-term clinical and radiological follow-up is mandatory.

Adolescent↗
PubMed1997

KRAS oncogene mutations suggest a common histogenetic origin for pleomorphic giant cell tumor of the pancreas, osteoclastoma of the pancreas, and pancreatic duct adenocarcinoma.

Giant cell neoplasms of the pancreas are rare tumors of uncertain histogenesis. Mutation of the KRAS oncogene is common in typical pancreatic duct adenocarcinoma. We have analyzed DNA from five pancreatic tumors with giant cells for mutations in the KRAS oncogene and found alterations of the second position of codon 12 in each case (four G > A transitions and one G > C transversion). The common mutation pattern in tumors with giant cells and duct adenocarcinoma suggests a common route to malignant transformation and may indicate a shared histogenesis. We also tested 11 cases of malignant fibrous histiocytoma, a histological mimic of pleomorphic giant cell tumor, for mutations in the KRAS oncogene. The absence of KAS mutations in each of the malignant fibrous histiocytomas (MFHs) and in other histologically similar tumors may provide assistance in the differential diagnosis of pleomorphic pancreatic tumors.

Adenocarcinoma↗
PubMed2002

Genetic imbalances in pleomorphic xanthoastrocytoma detected by comparative genomic hybridization and literature review.

Pleomorphic xanthoastrocytoma (PXA) is a rare, low-grade astrocytic tumor found in the central nervous system. Histologically, the tumor is characterized by markedly pleomorphic and lipidized cells. Although most of the patients have a favorable prognosis, a small number of cases undergoing recurrence or progression to anaplastic astrocytoma were reported. Very few genetic studies have been performed on PXA because of its rarity and the pathogenesis of this neoplasm is largely unknown. In order to provide an overview of genetic alterations in PXA, we performed comparative genomic hybridization to identify chromosomal imbalances (DNA gains and losses) in three cases of PXA. Genetic imbalance was detected on at least one chromosome for each case. One case, which revealed multiple genetic alterations, showed a poor prognosis. DNA gain on chromosome 7 and loss on 8p were demonstrated in two of three cases, suggesting that the candidate gene(s) located on these regions may play a role in the development of PXA. Further studies are needed to identify the residing candidate genes that are involved in the tumorigenesis of PXA. In addition, the histopathological features and previous genetic studies on PXA are reviewed.

Adult↗
PubMed1997

Cytogenetic and molecular genetic analysis of a pediatric pleomorphic sarcoma reveals similarities to adult malignant fibrous histiocytoma.

Cytogenetic and molecular genetic studies were performed on a pleomorphic sarcoma removed from the left atrium of a 15-year-old girl. Histologic analysis was consistent with a storiform-pleomorphic malignant fibrous histiocytoma (MFH). Although MFH is the most common soft-tissue sarcoma of late adulthood. It is extremely rare in childhood and its existence in the pediatric population remains controversial. Cytogenetic analysis revealed several alterations previously associated with adult MFH, including abnormalities of chromosomal bands 11p11 and 19p13. Moreover, the tumor demonstrated homogeneously staining regions (HSR) and double minute chromosomes (dmin) suggestive of gene amplification. We therefore screened the case for amplification of genes localized to chromosomal bands 12q13-14, including the putative protooncogenes MDM2, CDK4, SAS, CHOP, and CLI, which are frequently amplified and overexpressed in adult MFH. Southern and Northern blot analysis confirmed the coamplification of MDM2, CDK4, SAS, and CHOP. To our knowledge, such coamplification studies of the 12q13-14 amplicon have not been previously detected in pediatric MFH. Our results provide cytogenetic and molecular genetic evidence that pediatric and adult MFH are histogenetically related entities.

Adolescent↗
PubMed1997

Molecular characterization of a complex chromosomal rearrangement in a pleomorphic salivary gland adenoma involving the 3'-UTR of HMGIC.

Recently, the high mobility group protein gene, HMGIC, was identified as a common genetic denominator in benign tumors with chromosome 12q13-15 aberrations, such as lipomas, uterine leiomyomas, pleomorphic adenoma of the salivary glands, hamartomas of breast and lung, angiomyxomas, and endometrial polyps. In most cases, the rearrangements resulted in the separation of the three HMGIC DNA-binding motifs from the acidic carboxy-terminal tail. Here, we report about the molecular characterization of a case of pleomorphic adenoma carrying a t(1;12)(p22;q15). Studies were performed on a cell line derived from the primary tumor, i.e., cell line Ad-312/SV40. Although the chromosome 12 breakpoint was initially mapped more than 1 Mb distal to the HMGIC gene by fluorescence in situ hybridization (FISH) analysis, the present molecular studies reveal a more complex chromosomal rearrangement that directly affects the HMGIC gene. Using 3'-RACE analysis, a HMGIC fusion transcript was detected that contained the complete HMGIC, coding region but lacked the putative mRNA destabilizing AUUUA motifs that are normally present in the 3'-UTR of HMGIC. Wild-type HMGIC transcripts were also detected in the tumor cells. The results suggest that alterations in the 3'-noncoding region of HMGIC may have to be considered as pathogenetically relevant.

Adenoma↗
PubMed2000

Comparative cytogenetic study of spindle cell and pleomorphic leiomyosarcomas of soft tissues: a report from the CHAMP Study Group.

Leiomyosarcomas (LMS) of soft tissues frequently show complex karyotypic changes, and no specific aberration has been identified. The aim of this study was to search for recurrent chromosome aberrations in soft tissue LMSs and to correlate these, if present, with morphological and clinical parameters. From a series of soft tissue sarcomas thoroughly reexamined cytogenetically and histopathologically, 45 LMSs were retrieved; 35 were classified microscopically as spindle cell, 3 as epithelioid, and 7 as pleomorphic. Clonal chromosome changes were present in 14, 3, and 3 cases, respectively. This series was combined with 11 previously published, karyotypically abnormal pleomorphic LMSs for cytogenetic-clinico-histopathological correlations. The breakpoints were widely scattered, with no predilection of any of the recurrent breakpoints and losses to any of the morphologic subtypes. Combining numerical and unbalanced structural changes, the most frequently lost segments were 3p21-p23 (11 cases), 8p21-pter, 13q12-q13, 13q32-qter (10 cases each), 1q42-qter, 2p15-pter, 18p11 (9 cases each), 1p36, 11q23-qter (8 cases each), and 10q23-qter (7 cases). The most frequent gain was 1q12-q31 (6 cases). There was a greater frequency of losses in 1p and 8p and a lower frequency of losses in 10q and 13q in tumors that had metastasized than in localized tumors. We conclude that LMSs with clonal abnormalities display highly complex karyotypic changes and extensive heterogeneity. No significant correlation exists between these changes and age and sex of the patients, or with depth of tumor, topography, microscopic subtype, or tumor grade. Losses in 1p36 and 8p21-pter may be associated with increased risk of metastases. Comparison of our findings in soft tissue LMS with those previously reported in LMS in other locations suggest that the karyotypic profile is more dependent on site of origin than on microscopic features.

Adult↗
PubMed1992

Out-of-hospital pleomorphic ventricular tachycardia and resuscitation: association with acute myocardial ischemia and infarction.

Pleomorphic ventricular tachycardia is characterized by QRS complexes with repeated variation in polarity, amplitude, and regularity. When associated with prolongation of the QT interval, the term torsades de pointes is used to describe the arrhythmia. It usually is seen clinically in association with class IA antiarrhythmic drugs such as quinidine and procainamide, bradycardia, hypokalemia, and, much less often, other drugs and electrolyte disorders as well as a result of congenital and neurogenic causes. It also may accompany acute myocardial infarction or ischemia. We describe four patients in whom pleomorphic ventricular tachycardia was observed as the presenting rhythm or during the course of resuscitation in out-of-hospital cardiac arrest. In all four patients, acute myocardial ischemia appeared to be the provocative mechanism. Therapeutic implications include an awareness of the unusual behavior of this arrhythmia, especially its propensity to terminate spontaneously. Such awareness may prevent the delivery of unnecessary defibrillatory shocks.

Acute Disease↗