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PubMed1993

Spindle-cell non-pleomorphic atypical fibroxanthoma: analysis of a series and delineation of a distinctive variant.

Atypical fibroxanthoma is a bizarre, cytologically malignant but usually clinically benign, lesion which typically arises in sun-damaged skin of the head and neck region in the elderly. Classically, its morphology is said to represent the dermal counterpart of pleomorphic malignant fibrous histiocytoma. We have identified 10 cases of a more monomorphic spindle-celled, fascicular variant which, paradoxically, was often mistaken for a clinically malignant lesion because it lacked the pleomorphism of conventional atypical fibroxanthoma. These tumours all arose in the head and neck region as polypoid lesions in the elderly. The tumours were confined to the dermis, often had an epidermal collarette, showed an eosinophilic fascicular morphology and were highly mitotic. All 10 were vimentin positive and five showed very focal actin positivity. Desmin, keratin and S-100 protein were negative in all cases. The clinical course was benign in all cases, justifying their accurate recognition. The principal differential diagnoses are spindle cell squamous carcinoma, spindle cell melanoma and leiomyosarcoma. Immunohistochemistry plays a key role in this distinction.

Aged↗
PubMedDate not supplied

Pleomorphic xanthoastrocytoma in a 62-year-old male.

Pleomorphic xanthoastrocytoma has been described as a distinct clinicopathological entity with a relatively favourable prognosis. However, tumours closely resembling this entity have been shown to have the potential for aggressive behaviour, and to represent, on closer scrutiny, a number of disparate neoplasms. A case is described which, although otherwise typical of pleomorphic xanthoastrocytoma, occurred in a man of 62 years, and it is suggested that it should be considered a specific histological, rather than a clinicopathological entity.

Astrocytoma↗
PubMed2004

Conditional entropy as an indicator of pleomorphism in astrocytic tumors.

The entropies of nuclear arrangements as an indicator of pleomorphism are assessed using a morphometric method. Sixty astrocytic tumors (grades I, II, III and IV; 15 cases each) were reviewed and analyzed. All slides were stained with HE and MIB-1 antibody. The MIB-1 labeling index (LI) was assessed by counting nuclei under a microscope. Images of HE-stained slides were digitized and segmented using the watershed algorithm. Then, six nuclear parameters were measured automatically: (i) the number of total nuclei in the image, (ii) percentage of total nuclear area in the image, (iii) the mean area of the nucleus, (iv) the standard deviation of the area of the nucleus, (v) the entropy of nuclear arrangement (Entropysimple), and (vi) conditional entropy of nuclear arrangement (Entropyconditional). Entropysimple was defined according to the area of the nucleus and Entropyconditional was defined according to both the area of the nucleus and the area of its neighboring nuclei. Image processing and image analysis were performed with public domain software developed in the laboratory. Segmentation of the images resulted in inappropriate segmentation in a few percent of the images. The measurements obtained for each parameter were classified using discriminant analysis. The percentage of correct classification with Entropyconditional was 62%, which was the highest value among all the measurements. Classification based on the combination of all measurements resulted in a rate of correct classification of 88%. Thus, conditional entropy of nuclear arrangement is useful for grading of astrocytic tumors and it is proposed as an indicator of pleomorphism.

Astrocytoma↗
PubMed2006

Pineal parenchymal tumor of intermediate differentiation with cytologic pleomorphism.

We report a case of pineal parenchymal tumor in a 33-year-old man incidentally detected by radiological examination. The MRI showed an unhomogeneously enhanced, small tumor (approximately 1 cm in size) in the pineal region. A tumor specimen was obtained at endoscopic biopsy. Routine histology showed a highly cellular tumor characterized by a predominance of small cells showing high nuclear : cytoplasmic ratio and moderate nuclear atypia, pleomorphism including giant cells and an absence of pineocytomatous rosettes. Mitotic figures were rare (approximately 1 per 10 high-power fields). Tumor necrosis was not evident. Immunohistochemically, the neoplastic cells showed positivity for neural markers (neurofilament protein, synaptophysin) and pinealocyte-associated antibodies (PP1, PP5, PP6), but not for glial fibrillary acidic protein or S-100. The MIB-1 labeling index was relatively high (6.3%). Ultrastructurally, there was some evidence of pinealocytic differentiation, such as vesicle-crowned rodlets (synaptic ribbons) and paired twisted filaments in neoplastic cells. Thus, the tumor was confirmed as a pineal parenchymal tumor of intermediate differentiation by histology, immunohistochemistry and electron microscopy. This case indicates that marked cytologic pleomorphism can occur in pineal parenchymal tumors of intermediate differentiation.

Adult↗
PubMed1987

Ultrastructural characteristics of a pleomorphic liposarcoma. A possible involvement of myofibroblast.

A pleomorphic liposarcoma originated from the epicardial fatty tissue was studied with an electron microscope. The transmission electron microscopic examination revealed fibroblastic, myofibroblastic and primitive mesenchymal cells. Fibroblastic cells characterized by irregular nucleus with abundant heterchromatin and dilated cisternae were most frequently encountered, and the myofibroblastic cells, secondly in frequency, contained bundles of microfilaments with occasional dense bodies and outlined by discontinuous thin basal lamina. The primitive mesenchymal cells had mainly oval nucleus and electron lucent cytoplasm with poorly to moderately developed cell organellae. Some of the multinucleated giant cells relatively frequently observed revealed the aggregates of filaments with dense bodies at the cell margin. Many of them, irrespective of cell types, contained lipid droplets in the cytoplasm with various sizes. These observations suggest that a pleomorphic liposarcoma, at least a few of them, might contain not only fibroblastic, primitive mesenchymal but also myofibroblastic tumor cells with morphological varieties.

Aged↗
PubMed1988

A new human pleomorphic hepatocellular carcinoma cell line, KYN-2.

A new human hepatocellular carcinoma (HCC) cell line, KYN-2, has been established from a surgical specimen obtained from a 52-year-old Japanese male HCC patient. The originally resected HCC was classified as pleomorphic HCC corresponding to Edmondson-Steiner's grade III with a thick trabecular to solid arrangement. The cell line has been maintained for 17 months through 35 passages. Morphologically, the KYN-2 cells have retained the characteristics of the original HCC, being pleomorphic and composed of various types such as cells with relatively small, polygonal, eosinophilic cytoplasm and oval-shaped nuclei with a marked tendency to pile up, flat cells with abundant clear cytoplasm and oval-shaped nuclei, and many multinucleated giant cells, proliferating in a pavement-like cell arrangement. Some junctional complexes and a number of microvilli are evident between the cells by electron microscopy. Functionally, these cells were found to secrete albumin, alpha 1-acid glycoprotein, alpha 1-antitrypsin, ceruloplasmin, transferrin, complement C, fibrinogen, fibronectin, prothrombin, retinol-binding protein (serum type), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), ferritin and beta 2-microglobulin in chemically defined medium (CDM). The secretion of AFP and CEA is apparently dependent upon culture medium and passage. The doubling time of cells growing in serum-containing medium at the 14th passage was 84 h, and those of cells in serum-containing medium, HB101 (serum-free medium) and CDM at late passage were 28, 68, and 42 h, respectively. Chromosome analysis revealed that the chromosome number ranged from 56 to 69 without a mode, and the presence of marker chromosomes. HB virus DNA sequence was not detected by hybridization analysis. The tumorigenicity of KYN-2 cells was identified by development of tumors in nude mice after subcutaneous injection of the cells; the tumors showed an appearance basically similar to that of the original HCC. Thus, these findings suggest that the KYN-2 cell line is available as a new human HCC cell line and should be useful for various studies on HCC.

Animals↗
PubMed1997

Pleomorphic hyalinizing angiectatic tumor of soft parts.

A case of recently described pleomorphic hyalinizing angiectatic tumor (PHAT) of soft parts is reported. The subcutaneous solid tumor arising in the axilla of a 58-year-old man was histologically characterized by sheets of mitotically inactive oval and pleomorphic cells, intranuclear cytoplasmic inclusions, and clusters of ectatic vessels with perivascular hyalinization. Mono- and multinucleated giant cells were also present. A hemangiopericytoma-like pattern of vascularity, pseudovascular spaces, stromal collagen with degenerative changes, and immunoreactivity for CD34 were observed. Since these features were very similar to those of solitary fibrous tumors of various sites and newly categorized giant cell angiofibroma, it is considered that PHAT, solitary fibrous tumor, and giant cell angiofibroma may be in the same family of tumor. The tumor was diploid with a low S-phase fraction. The patient was well with no evidence of disease for 23 months.

Antigens, CD34↗
PubMed2006

Pleomorphic lobular carcinoma in situ of the breast composed almost entirely of signet ring cells.

Some examples of lobular carcinoma in situ (LCIS) may be composed in part of signet ring cells. Such proliferations have been considered examples of pleomorphic LCIS based on pathological features of the more conventional component. However, the occurrence of LCIS composed entirely of signet ring cells is extraordinarily rare. This report describes an example of an in situ proliferation that was composed almost entirely (>95%) of signet ring cells, which was unassociated with an invasive carcinoma and which showed comedo-type necrosis. There was only focal lobulocentric distention by lesional cells, as is typical of classic LCIS. However, discrete, ductal-type cross-sectional profiles showed a purely intraepithelial proliferation of remarkably discohesive signet ring cells. The signet ring cells had intermediate-grade nuclear atypia, no significant mitotic activity and were positive for mucicarmine and PAS stains (the latter with and without diastase predigestion). The cells displayed marked immunoreactivity for high-molecular-weight keratin (stained by 34beta E12 antibody), MUC1, gross cystic disease fluid protein-15, cytokeratin 7 and were negative for cytokeratin 20, E-cadherin, progesterone receptor and HER2/neu. It is concluded that this is an example of a purely signet ring variant of pleomorphic LCIS.

Adult↗
PubMed1981

A pleomorphic lipoma in the scalp.

The pleomorphic lipoma is a benign neoplasm of lipocytes with atypical histologic features. The tumor shows a predilection for the region of the neck and shoulders of midde-aged and elderly men and must be differentiated from similar-appearing malignant entities such as liposarcoma and malignant myxoid fibrous histiocytoma. An occurrence of a pleomorphic lipoma in the scalp is reported and its histologic features described and discussed.

Humans↗
PubMed1992

Pleomorphic lipoma. Case reports and review of the literature.

Two patients are reported with pleomorphic lipoma, a benign subcutaneous fatty tumor showing atypia in which histologic diagnosis may be difficult. The tumors are well circumscribed lesions, most commonly occurring in the neck and shoulder of middle aged men. An important histologic criteria is the presence of floret-like multinucleated giant cells embedded in a myxoid stroma. Pleomorphic lipoma may be confused with several malignant soft-tissue neoplasms, including myxoid malignant fibrous histiocytoma and variants of liposarcoma. It is important to establish the correct diagnosis to avoid unnecessary radical surgery.

Forehead↗
PubMed1999

Immunohistochemical characterization of pleomorphic giant cells in basal cell carcinoma.

Over 20 cases of basal cell carcinomas with pleomorphic giant cells of the mononuclear or multinucleate type have been described. The nature of these cellular and nuclear changes has not been elucidated. Some authors found that these cells have phagocytic properties and others reported an aneuploid DNA content. We have seen mitotic figures in some of these giant cells, and postulate that these cells are capable of proliferation. Twelve cases of basal cell carcinoma with pleomorphic giant cells were examined using monoclonal antibodies recognizing the proliferating cell nuclear antigen (PCNA), Ki-67, and bcl-2 antigens. Expression of proliferation associated antigens in the giant cell population was higher than in the small cell population. Over expression of bcl-2 was detected in both the small and giant cells in all cases. The results demonstrate that the giant tumor cells are cycling and express bcl-2 protein in a manner consistent with basal cell carcinoma. The changes are unlikely to represent a senescent change as seen occasionally in mesenchymal neoplasms.

Adult↗
PubMed2006

Pleomorphic lipoma of the face: case report.

Pleomorphic lipoma is an uncommon variant of lipoma, which microscopically may resemble a liposarcoma. However, it is a slow-growing and well-circumscribed lesion with a benign behavior. Therefore, recognizing this entity is extremely important to perform the proper treatment. We present an additional case of pleomorphic lipoma in the face, which to our knowledge seems to be the 11th case reported in the English-language literature.

Aged↗
PubMed1985

Intermediate filaments in cultured human pleomorphic adenomas. An immunohistochemical study.

Primary cultures of 9 benign human pleomorphic adenomas were analyzed by immunofluorescence and antibodies against the different intermediate filaments and microfilaments. The cultured cells were also cytogenetically characterized by G- and C-banding techniques. The adenoma cells expressed at least three different classes of intermediate filaments, viz. prekeratin, vimentin and glial fibrillary acidic protein (GFA). No correlation between chromosomal pattern and intermediate filament expression was found. The frequency of cells stained for each of the different antibodies varied considerably among the tumours. Prolonged culturing appeared to induce a reduction of cells positive for prekeratin. This was probably a true loss of antigens and not an effect of overgrowth of stromal cells. It is concluded that the cells studied, on the basis of several criteria, are of neoplastic origin. This in vitro system appears to be well suited for further histogenetic studies on pleomorphic adenomas.

Actin Cytoskeleton↗
PubMed1991

Pleomorphic adenoma of the breast. Case report.

A clinicopathologic study of a pleomorphic adenoma of the breast is presented and attention is drawn to a previously unreported association with a cyst. Malignancy was strongly suspected in the light of radiologic features. Immunohistochemistry stresses the similarity between pleomorphic adenoma of salivary gland and breast. A common histogenesis of the two entities is also suggested. Ontogenetic links of both glands are mentioned.

Adenoma↗
PubMed1992

Altered expression of ABO (H) carbohydrate antigens is seen in pleomorphic adenomas.

Cell surface carbohydrate antigens show changes in relation to differentiation, maturation and malignant transformation. The expression of type 2 chain ABH carbohydrate structures of the ABO histo-blood group system was investigated in 28 pleomorphic adenomas (PA) and normal parotid glands in order to study possible changes in the glycosylation pattern. The distribution of carbohydrate structures was investigated by immunohistological stainings of formalin-fixed paraffin-embedded material using monoclonal antibodies (MAbs) with well-defined specificity. A strong interindividual variation was found in the normal tissue as well as in the tumors. In normal tissue, acinus and duct cells all expressed elongated carbohydrate structures. The yoepithelial cells did not stain with any of the MAbs investigated. In the PAs, staining was seen in the ductular structures and myoepithelial cells. In contrast to normal tissue, the tumors expressed the short precursor molecule sialylated N-acetyllactosamine. Furthermore, the PAs showed loss of H and A antigens, and a reduced expression of Le(y) compared to normal tissue. The ductular structures as well as the modified myoepithelial cells expressed binary N-acetyllactosamine, which in the normal tissue could only be found in the striated and excretory ducts. Thus our study has shown that aberrant glycosylation is not only a feature of malignant neoplasms but also occurs in pleomorphic adenomas.

ABO Blood-Group System↗
PubMed1993

Pleomorphic xanthoastrocytoma: the birth of a diagnosis and a concept.

This review deals with one of the newly adopted entities in the second edition of the histologic typing of CNS tumours by the World Health Organization: pleomorphic xanthoastrocytoma and reviews the clinical features, gross and microscopic characteristics as well as the common and some of the unusual variants of this tumor. The steps and events leading to the recognition of the basic character of this neoplasm and its designation as an independent entity are recollected and a few characteristic MRI scans and photomicrographs of pleomorphic xanthoastrocytomas are provided.

Astrocytoma↗
PubMed1974

Culture purity assessments and morphological dissociation in the pleomorphic microorganism Bacterionema matruchotii.

The inherent pleomorphism of Bacterionema matruchotii resulting from its mode of reproduction was enhanced by temporal effects of culture age and growth condition and by the more lasting effects of rough to intermediate to smooth morphological dissociation. Routine morphological observations with a single growth condition were inadequate to permit unambiguous judgements of culture purity. Multiple criteria were required. Pleomorphism and the undetected presence of contaminants in primary and successive cultures of B. matruchotii can explain the emergence of unrelated bacteria from B. matruchotii reported previously by others and ascribed to genetic instability.

Actinomyces↗
PubMed1992

Pleomorphic adenoma of the lacrimal gland.

To reduce the risk of recurrence and malignant transformation, pleomorphic adenomas of the lacrimal gland should be removed intact, without prior biopsy. Seventy one of the 78 patients in this series were referred without previous surgery, and, on clinical or radiological evidence, 63 (89%) tumours were correctly diagnosed and totally excised, with preservation of a margin of the surrounding normal tissue. Sixty three patients had tumour within the body of the gland and 55 (84%) had radiological signs or satisfied clinical criteria for pleomorphic adenoma that we suggested previously; that is, over 1 year of symptoms and absence of pain. Eight (16%) orbital lobe tumours were misdiagnosed preoperatively and biopsied; in all these patients symptoms had been present for less than 1 year, and four patients had pain. Eight patients with tumours arising in the palpebral lobe had a short history of an upper lid mass, and their tumours were excised without biopsy. With the surgical techniques described in this paper, there has been no recurrence of tumour in patients with follow-up as long as 21 years. A modification of surgical technique, with preservation of the palpebral lobe of the gland, has reduced the incidence of postoperative dry eye and distortion of the upper eyelid.

Adolescent↗