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PubMed1992

HTLV-1-negative pleomorphic T-cell lymphoma of the skin: the clinicopathological correlations and natural history of 15 patients.

The peripheral T-cell lymphomas represent a heterogeneous group and include, besides mycosis fungoides and Sézary syndrome, large-cell anaplastic lymphoma. We report 15 cases from our files that fulfil the histological criteria of pleomorphic T-cell lymphoma with primary skin involvement. Most of the cases were elderly with a male-to-female ratio of 1.5:1. The HTLV-1 serology was negative. The clinical features of these patients differed from those with mycosis fungoides and Sézary syndrome, in that eczematous and precursor lesions such as parapsoriasis en plaque were lacking apart from one exception. All the patients with small-cell pleomorphic T-cell lymphomas were alive, although three of the nine patients with medium-to-large tumour cells have died. Pleomorphic T-cell lymphoma should be regarded as a distinct entity among the lymphoproliferative disorders of the skin.

Adult↗
PubMed1996

pp32 overexpression induces nuclear pleomorphism in rat prostatic carcinoma cells.

Nuclear pleomorphism is an important diagnostic factor in tumour pathology. Traditionally, nuclear pleomorphism is evaluated qualitatively or semiquantitatively, often as a component of tumour grade; the molecular basis of nuclear pleomorphism, however, remains unclear. In this study, we investigated the quantitative effects on nuclear morphology of overexpressing pp32, a recently described nuclear phosphoprotein highly expressed in self-renewing and neoplastic cell populations. Assessment of Feulgen-stained transfected and control lines of AT3.1, a rat prostatic carcinoma cell line, using a computerized Cellular Image Analysis System (BD CAS-200) showed that stable overexpression of human pp32 in AT3.1 cells is accompanied by marked increases in the coefficient of variation of nuclear shape, nuclear size and chromatin textures but not in DNA content. In contrast, stable transfection with control vector, with ras, or with bcl-2 failed to affect nuclear morphology. Cell cycle analysis further showed that pp32-related increases in variation of nuclear structure manifested principally in G1. These studies suggest that pp32 plays a role either directly or indirectly in the control of nuclear shape of G1 cells.

Animals↗
PubMed1992

Pleomorphic lipoma. Case report and discussion of "atypical" lipomatous tumors.

A case of pleomorphic lipoma is described. Pleomorphic lipoma is included in the "atypical" lipoma classification. Because of its atypical microscopic appearance, it must be differentiated from liposarcoma. We will discuss pleomorphic lipoma and its position in the classification of atypical fatty tumors.

Glycosaminoglycans↗
PubMed1993

Prognostic value of nucleolar size and size pleomorphism in choroidal melanomas.

Morphometric estimates of nucleolar size have been shown to possess a high prognostic value in patients with uveal melanomas. The authors investigated various quantitative estimators of the mean size and pleomorphism of nucleoli in choroidal melanomas from a consecutive series of 95 Danish patients treated solely by enucleation of the melanoma-bearing eye in the period from 1977 to 1979. The independent prognostic value of the quantitative histopathological variables was evaluated using multivariate Cox analysis. Apart from patient data and information about tumor extent, histological type of melanoma, and largest macroscopic tumor dimension (LTD), the following histomorphometric estimates were obtained: mean diameter of the 10 largest nucleoli (MLN), point-sampled mean nucleolar profile area (nucleolar ao) and the associated standard deviation of nucleolar ao, the volume-weighted mean nucleolar volume (nucleolar vv), and associated variance and relative variance of nucleolar volume (nucleolar Varv(v) and nucleolar CVv(v), respectively). The intra-observer reproducibility of estimates of nucleolar vv was tested in 20 cases and found acceptable (r = 0.84, 2p = 3.6.10(-6)). Correlation analysis indicated that estimates of nucleolar vv and nucleolar Varv(v) are identical in choroidal melanomas, except for a scaling factor. There were no differences of the grouped means of histomorphometric estimates in choroidal melanomas that showed intra- or extra-ocular extension (2p > 0.13). LTD was of the same magnitude in all histological types of melanoma (2p = 0.69). Estimates of nucleolar vv and associated estimates of nucleolar volume pleomorphism were increased in melanomas of the mixed and epitheloid cell type (2p < 0.005). Single factor analyses showed that all quantitative histopathological variables were of prognostic value in the studied patients, in addition to the histological type of tumor. However, using multivariate analysis, only estimates of LTD, MLN, nucleolar vv, and of nucleolar volume pleomorphism had independent prognostic value.

Cell Nucleolus↗
PubMed1984

Pleomorphism of fusobacteria isolated from the cockroach hindgut.

Fusobacteria are commonly isolated from the hindgut of the cockroach Eublaberus posticus . Eleven strains isolated from E. posticus by us were keyed to four species, Fusobacterium necrophorum, F. varium , F. gonidiaformans , and F. prausnitzii , using current taxonomic criteria. With the exception of F. gonidiaformis , all species showed rods with swollen centers and large bodies. The pleomorphism of F. varium was examined by phase microscopy and scanning and transmission electron microscopy. The pleomorphic process begins with a gradual swelling at the center of the rod until a large round body is formed. Some of these round bodies then fragment, giving rise to rod-shaped cells. When 10% yeast extract was added to growth media, pleomorphism was not induced. A dialyzable factor was found to account for this observation. Fermentation of [1-14C]glutamic acid gives rise to butyrate labeled in the carboxyl carbon, indicating that butyrate is formed by the hydroxyglutarate pathway which may be characteristic for the genus Fusobacterium.

Animals↗
PubMed1996

Clinical, radiological, and therapeutic features of pleomorphic xanthoastrocytoma: report of three patients and review of the literature.

Two out of three patients with pleomorphic xanthoastrocytoma were initially misdiagnosed and correctly interpreted only at tumour recurrence, with progression to malignancy in one. The third patient presented with a remarkably long history of epilepsy. Pleomorphic xanthoastrocytoma is a low grade astrocytoma that is still confused with other tumours. Because pleomorphic xanthoastrocytoma can become malignant even after many years of benign behaviour, a long term follow up is necessary.

Adolescent↗
PubMed2004

Pleomorphic carcinoma of lung: comparison of CT features and pathologic findings.

PURPOSE: To retrospectively evaluate computed tomographic (CT) features of pleomorphic carcinoma of the lung and to compare these features with pathologic findings. MATERIALS AND METHODS: Ten patients (10 men, three women; mean age at diagnosis, 64.1 years; range, 43-75 years) with pleomorphic carcinoma treated from June 2000 to January 2003 were selected from two institutions. Two radiologists retrospectively reviewed CT features, which included size and location of tumor, presence of calcification, attenuation values and internal architecture of the mass, and invasion of pleura and chest wall. Attenuation values of the mass on CT scans were compared with pathologic findings in tumors in available gross specimens. Follow-up CT scans were not routinely obtained except in two patients with progressive pleural effusion and rapid growth of the tumor as seen on serial chest radiographs. RESULTS: On unenhanced CT scans, attenuation of the tumor was similar to that of the surrounding muscle. Calcification within the tumor was visible in one patient. Invasion of chest wall was noted in two patients. Seven patients had pleural invasion. Tumors were located at the lung periphery in nine patients. On contrast material-enhanced CT scans, lesions with the longest diameter larger than 5 cm showed central low-attenuation areas with substantial enhancement in the tumor periphery; in comparison, lesions with the longest diameter smaller than 5 cm showed homogeneous enhancement. Size of two lesions with the longest diameter larger than 5 cm increased rapidly after a follow-up of shorter than 3 weeks. Low-attenuation areas on contrast-enhanced CT scans were found to correspond to areas of myxoid degeneration, necrosis, or hemorrhage in pathologic specimens. CONCLUSION: Findings of this study suggest that pleomorphic carcinomas of the lung preferentially manifest as large peripheral lung neoplasms with a central low-attenuation area and frequently invade the pleura and chest wall.

Adult↗
PubMedDate not supplied

Aspiration biopsy of pleomorphic lipoma of the breast. A case report.

BACKGROUND: It is well known that subcutaneous lumps in the breast may create diagnostic confusion. We report, for the first time in the cytologic literature, the features of a pleomorphic lipoma in the breast. CASE: Pleomorphic lipoma of the breast was aspirated, showing typical floret cells and mononuclear, hyperchromatic cells with scalloped nuclei, masquerading as malignancy. CONCLUSION: Pleomorphic lipoma has rather typical cytologic features that may allow its recognition when they are present in the proper clinical setting. This report illustrates another diagnostic pitfall in fine needle aspiration biopsy of the breast.

Biopsy, Needle↗
PubMedDate not supplied

Diagnostic pitfalls in fine needle aspiration cytology of pleomorphic lipoma. A case report.

BACKGROUND: Pleomorphic lipoma is an unusual pseudosarcomatous condition with characteristic morphology. Despite its pleomorphic appearance, it follows a benign course and does not recur or metastasize if completely excised. CASE: A 66-year-old man presented with swelling in the back of the neck of approximately six months' duration. The focally cellular aspirate revealed round to oval, hyperchromatic cells, rare multinucleated cells and fragments of mature adipose tissue. On initial evaluation, the smear pattern suggested a malignant neoplasm. However, upon review of the cytologic material along with histology, the characteristic pattern, including floret cells, was recognized. CONCLUSION: The rarity of pleomorphic lipoma and the atypical cellular features of the aspirate can cause difficulty in diagnosing this entity. Awareness of this rare but not-uncommon entity, along with clinical correlation, is crucial in arriving at the correct diagnosis.

Aged↗
PubMed2003

Pleomorphic adenoma of minor salivary gland in the parapharyngeal space.

BACKGROUND: Majority of tumours occurring in minor salivary gland are malignant. Pleomorphic adenoma is of rare occurrence in parapharangeal space. CASE PRESENTATION: A rare case of a minor salivary gland pleomorphic adenoma of the parapharyngeal space is reported. Review of literature, clinical features, pathology, radiological findings and treatment of these tumours are discussed. CONCLUSIONS: Parapharangeal salivary tumours presents as a painless progressive swelling with majority of these being malignant. Pleomorphic adenoma in parapharangeal space is of rare occurrence. Complete surgical excision is the treatment of choice.

Journal Article↗
PubMed2004

Concurrent pleomorphic adenoma in parapharyngeal space and submandibular gland.

BACKGROUND: Pleomorphic adenoma in the parapharyngeal space either occurs de novo or as an extension from the deep lobe of the parotid gland. CASE PRESENTATION: A rare synchronous occurrence of pleomorphic adenoma in the parapharyngeal space and submandibular gland of a 48-year-old Nigerian male is reported. CONCLUSION: Pleomorphic adenoma concurrent in the parapharyngeal space and submandibular gland is very rare. A complete surgical excision of both tumors is the treatment of choice.

Journal Article↗
PubMed2000

A pleomorphic adenoma of the lacrimal gland in a dog.

A 13-year-old female mongrel dog had a pleomorphic adenoma of the lacrimal gland in the right upper orbit. The tumor measured 3.8 x 3.0 x 3.3 cm, appeared white, round, and firm, and pressed the right globe and surrounding tissues. Histopathologically, the tumor had a thin connective tissue capsule and was composed of tubules with two cell types, some resembling luminal epithelial cells making up the tubular structures and the other of myoepithelial cells. Epithelial tubules were disposed in an adenomatous fashion and separated from each other by proliferating pleomorphic myoepithelial cells. Immunohistochemically, large numbers of the luminal epithelial cells revealed an immunopositive reaction against keratin/cytokeratin (AE1/AE3), and some epithelial cells reacted against cytokeratin 14. Spindle-shaped myoepithelial cells revealed an immunopositive reaction against cytokeratin 14, alpha-smooth muscle actin, and vimentin. A small number of myoepithelial cells reacted against desmin. S-100 protein immunopositivity was frequently found in luminal epithelial cells and rarely in the pleomorphic myoepithelial cells. Glial fibrillary acidic protein positivity was commonly found in myoepithelial cells, myxoid matrices, and intracystic materials, but not in luminal epithelial cells.

Actins↗
PubMedDate not supplied

Trypanosoma rangeli (Tejera, 1920): observations upon pleomorphism.

Meta-trypomastigotes of Trypanosoma rangeli Tejera, 1920, harvested from LIT medium, were inoculated i.p. or s.c. into 6, 16, and 26 g NMRI mice, these representing increasing degrees of immunological maturity. In all cases, similar pleomorphic patterns were observed. Four morphobiometrically differentiable types of trypanosome were encountered in an overlapping temporal sequence. These observations, taken in comparison with those on pleomorphism in this and other species of Trypanosoma by other workers, are consistent with the hypothesis that the pleomorphic types represent the natural development of the parasite, rather than the result of the immune response of the mammal host. Small, slender trypanosomes prevalent at the onset of the parasitemia either reinvade the tissue cells for relatively limited subsequent generations of tissue reproduction, or else differentiate toward the forms that are only capable of colonizing the insect vector.

Age Factors↗
PubMed2005

Pleomorphic carcinoma of the lung associated with loss of heterozygosity of p53 gene.

We report a case with pleomorphic carcinoma of the lung in a 70-year-old man. Pleomorphic carcinoma is characterized by a heterogenous composition that includes epithelial and mesechymal malignancies. In the present case, the tumor was composed of a mixture of unequivocal squamous cell carcinoma and spindle cell components resembling sarcomatous overgrowth. The spindle component did not include a heterologous mesenchymal element characterized by overt differentiation for bone, cartilage, neuron or muscle tissue. To evaluate a state of differentiation of the spindle cell component, we immunohistochemically examined expression of the antigens including vimentin, cytokeratin, sarcomeric actin, alpha-smooth muscle actin, S-100 protein, CD34, Factor VIII, and CD68. The results showed sole expression of vimentin in the spindle cell component, suggesting an immature state of the mesenchymal lineage. Furthermore, the spindle cell component of this case was genetically characterized by loss of heterozygosity (LOH) at a codon 234 of exon 7 of the p53 gene. This mutation causes an amino-acid replacement (Tyr to Cys), which was previously proven to attenuate p53 function. The present case may suggest a relation between somatic alteration of the p53 gene and histogenesis of pleomorphic carcinoma.

Aged↗
PubMed2002

Distinctive pleomorphic xanthoastrocytoma-like tumor with exclusive abortive or aberrant neuronal differentiation and repeated recurrence--case report.

A 9-year-old girl with a 1-month history of generalized seizure presented with a distinctive tumor resembling pleomorphic xanthoastrocytoma. Neuroimagings showed a right frontotemporal lobe tumor. Histological examination of the resected tumor indicated similarity to pleomorphic xanthoastrocytoma without staining for glial fibrillary acidic protein. The neuronal immunoreactivity and ultrastructural features showed two discrepancies: Numerous cytoplasmic processes containing rich structures suspected to be microtubules and neurofilaments were present, but neurofilament protein 70 kd/200 kd staining was negative; and many tumor cells showed synaptophysin staining, but no synaptic structures or vesicles were observed. She suffered recurrence 14 months after the first surgery. The specimen from the second operation revealed no malignant transformation with a MIB-1 labeling index of 1.9%. Only 2 months after the second operation, there was a second recurrence. Irradiation was administered (60.2 Gy). Twenty-eight months later, no tumor progression was seen. This tumor was an unconventional type with "abortive" or "aberrant" neuronal differentiation or an extreme variant of pleomorphic xanthoastrocytoma.

Astrocytoma↗
PubMed2006

Benign pleomorphic astrocytoma in the hypothalamus--case report.

A 41-year-old woman presented with an unusual case of benign astrocytoma with marked pleomorphism manifesting as consciousness disturbance due to intraventricular hemorrhage. Magnetic resonance imaging revealed a well-enhanced hypothalamic mass protruding into the third ventricle. Despite partial resection of the tumor without additional therapy, there have been no signs of tumor regrowth for 6 years. The histological findings revealed solid proliferation of tumor cells with marked pleomorphism, contrary to the benign clinical course. However, no mitosis, necrosis, or endothelial proliferation were found and the MIB-1 index was less than 0.5%. Immunohistochemical staining indicated the glial origin of the tumor. The tumor was similar to pleomorphic xanthoastrocytoma, but the histological findings were not exactly identical, indicating a new histological entity.

Adult↗
PubMed2005

CT findings of surgically resected pleomorphic carcinoma of the lung in 30 patients.

OBJECTIVE: The objective of our study was to assess the CT features of surgically resected pleomorphic carcinoma of the lung. CONCLUSION: The CT features of pleomorphic carcinoma of the lung appear to be dictated by the epithelial component of the tumor. Among the various subtypes of pleomorphic carcinoma, the large cell and giant cell subtype showed constant CT features including subpleural location, peritumoral areas of ground-glass attenuation, and extensive central low-attenuation areas.

Carcinoma, Non-Small-Cell Lung↗
PubMed1984

Pleomorphic carcinoma of the gallbladder: case report and ultrastructural study.

Carcinomas of the gallbladder with pleomorphic spindle cell histology are unusual. We report such an occurrence in a 47-year-old male with a neoplasm showing both a mixed squamous and a pleomorphic spindle cell pattern. Ultrastructural studies supported the likelihood that this lesion represented a pleomorphic carcinoma and revealed unique paracrystalline structures intimately associated with tonofilaments. For this reason we believe that this and some other previously diagnosed sarcomas and carcinosarcomas of the gallbladder are in reality poorly differentiated carcinomas of either adeno, squamous, or mixed type. This illustrates the need for critical ultrastructural assay to determine the nature of poorly defined and differentiated neoplastic growths.

Carcinoma↗