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PubMed2002

Carcinosarcoma of the parotid gland with epithelial-myoepithelial carcinoma and pleomorphic sarcoma components.

We report a case of true malignant mixed tumour (carcinosarcoma) of the parotid gland with epithelial-myoepithelial carcinoma and pleomorphic sarcomatous components in a 68-year-old woman. The pleomorphic sarcomatous component behaved aggressively with lymph node and distant metastases. The biological behaviour of the individual components in a malignant mixed tumour makes it difficult to diagnose. We could find no previous report of epithelial-myoepithelial carcinoma as a component of a carcinosarcoma of the parotid.

Aged↗
PubMed1995

A case of pleomorphic T-cell lymphoma with a high content of reactive histiocytes presented with hypereosinophilia.

A case of peripheral T-cell lymphoma classified, according to the updated Kiel classification, as a large pleomorphic T-cell lymphoma with a high content of reactive histiocytes and blood hypereosinophilia is reported. Light microscopic examination revealed a diffuse effacement of the lymph node structure by large pleomorphic lymphoma cells mixed with eosinophils and many histiocytes, some of them presenting discrete features of hemophagocytosis. The neoplastic cells were CD3, CD5, CD8 and HLA-DR positive but failed to show CD30 antigen. DNA molecular analysis displayed simultaneous rearrangements of the genes coding for the delta chain of the T-cell receptor and for the Ig heavy chain. Increased serum levels of angiotensin converting enzyme and ferritin were found and probably induced by the reactive histiocytes. Immunoassays (ELISA) with antibodies directed against some cytokines and against the Tac peptide (sIL-2R) were performed. They demonstrated high serum levels of sIL-2R and a slight increase in GM-CSF, but neither IL-5 nor IL-3. The association of blood hypereosinophilia and histiocytic hyperplasia with a peripheral T-cell lymphoma is discussed.

Adult↗
PubMed1999

Myofibroblastoma of the breast with hemangiopericytoma-like pattern and pleomorphic lipoma-like areas. Report of a case with diagnostic and histogenetic considerations.

Myofibroblastoma (MFB) of the breast is an uncommon benign spindle cell tumor which may exhibit a wide spectrum of histological features. We report an unusual case of MFB of the male breast, showing cellular areas with a hemangiopericytoma-like pattern similar to that observed in solitary fibrous tumor (SFT) and extensive fibromyxoid areas containing numerous atypical stromal cells. The association of these atypical cells with mature adipocytes and microcystic and/or myxoid degenerative changes resembled pleomorphic lipoma-like and myxoid liposarcoma-like features, respectively. To our knowledge, these peculiar morphological findings have not been previously reported in MFB of the breast. They should be recognized to avoid confusion with other mesenchymal tumors, especially with hemangiopericytoma, pleomorphic lipoma (PL), spindle-cell lipoma (SCL) and myxoid liposarcoma. A case of MFB of the breast showing morphological features also commonly seen in SFT and PL/SCL is further morphological evidence in support of the speculation that the mesenchymal tumors of the breast, also known under the terms benign spindle cell tumors, fibromas, SFTs, SCLs and MFBs, are histogenetically related lesions.

Biomarkers, Tumor↗
PubMed2003

Molecular genetic analysis of anaplastic pleomorphic xanthoastrocytoma.

A case of pleomorphic xanthoastrocytoma in a 10-year-old Malay boy is reported. The patient presented with headache and epilepsy. On computed tomography, a ring-enhancing low-density lesion was observed in the left fronto-temporal area. During surgery, a cystic tumour containing serous fluid was found and almost totally removed. Histologically, the tumour exhibited marked pleomorphism of oval and spindle-shaped cells intermixed with uni- and multinucleated giant cells, and xanthomatous cells with foamy cytoplasm. The tumour displayed pericellular reticulin and periodic acid-Schiff positive granules. Focally, six mitotic characters per 10 high-power fields were seen, and necrosis was confined only to the inner lining of the cyst. Mutational analysis showed that a frameshift mutation (a 4-bp deletion) in the p53 gene had occurred in codons 273 and 274 of exon 8. No mutation was detected in the p16 gene. No allelic loss and/or loss of heterozygosity were observed on chromosome 10 using microsatellite marker D105532. The patient was treated with postoperative radiotherapy because of histological anaplasia and the presence of residual tumour. The patient showed marked neurological recovery after a follow-up period of 2 years.

Astrocytoma↗
PubMed1995

Pleomorphic liposarcoma of the pterygomandibular space involving the maxilla.

Liposarcoma of the head and neck is rare. Because of its rarity, we report this case of pleomorphic liposarcoma of the left pterygomandibular space, involving the maxilla, maxillary sinus, left lateral maxillary wall, left maxillary gingiva with extension into the buccal space, retro-orbital region, left mandibular ramus, and left zygomatic process. To our knowledge, there are only two other reported cases of liposarcoma involving the maxilla, one of which was a pleomorphic liposarcoma. The pertinent literature is reviewed with an emphasis on the importance of histopathologic classification.

Adolescent↗
PubMed1988

Pleomorphic adenomas of the parotid gland: superficial parotidectomy or limited excision?

In this retrospective study of parotid tumours, 57 patients with pleomorphic adenomas were treated with superficial parotidectomy and 33 patients with limited excision. The follow-up period has been 4-14 years. When the operation was superficial parotidectomy, recurrences occurred in 8.7 per cent compared to 6 per cent in cases of limited excision. Side-effects such as permanent weakness of the facial nerve or post-operative gustatory sweating were also more common when superficial parotidectomy was performed. The post-operative results observed suggest that limited excision under magnification is more favourable than superficial parotidectomy in the treatment of pleomorphic adenomas.

Adenoma↗
PubMed1992

Ossifying pleomorphic adenoma of the maxillary antrum.

An unusual case of pleomorphic adenoma with exuberant bone formation, occurring in the maxillary antrum of a 21-year-old male and showing repeated recurrence, is reported. In contrast to the endochondral ossification in the previous reported cases of pleomorphic adenoma, direct deposition of osteoid by metaplastic myoepithelial cells is suggested to explain the bone formation. The difficulties of distinguishing this tumour from osteosarcoma during intraoperative diagnosis are discussed.

Adult↗
PubMed1998

Pleomorphic lipoma of the parotid gland.

Lipomata are rare tumours of the parotid gland. The pleomorphic lipoma represents an unusual histological variant of the benign lipoma. We report a case of a pleomorphic lipoma arising in the parotid gland. Only one case of a similar nature has previously been recorded. This tumour is benign, was fully excised and recurrence is not expected.

Aged↗
PubMed1997

Late sequelae of treated pleomorphic xanthoastrocytoma: malignant brain stem astrocytoma occurring 15 years after radiation therapy.

The pleomorphic xanthoastrocytoma (PXA) is a unique astrocytic neoplasm with an unexpectedly favorable prognosis despite striking pleomorphism of the cellular constituents. Although a majority of patients experience extended survival, these tumors may recur and some cases progress to high-grade astrocytoma. Recurrence inevitably involves the anatomic vicinity of the primary tumor. In this report, we describe a malignant brain stem astrocytoma that occurred 15 years after surgery and radiation treatment of a 16-year-old patient who had a temporal lobe PXA. To our knowledge, this is the first reported case of a malignant astrocytoma arising outside the primary anatomic site of a previously treated PXA and likely represents a radiation-induced secondary neoplasm.

Adolescent↗
PubMed2003

Solitary sclerotic fibroma of skin: a possible link with pleomorphic fibroma with immunophenotypic expression for O13 (CD99) and CD34.

BACKGROUND: Solitary sclerotic fibroma (SF) presents as a well circumscribed dermal nodule, composed of sparse spindle cells with alternating wavy collagen fibers arranged in a storiform pattern. The histogenesis and nature of this histologically distinct lesion are uncertain. Whether this peculiar tumor represents a true hamartoma or a degenerating end of various fibrous lesions such as pleomorphic fibroma (PF), dermatofibroma, or angiofibroma is still controversial. High proliferating index of spindle cells in SF argues against the possibility of being a degenerating end product of another lesion. METHODS: We studied morphological features and immunoprofile of eight SFs, in comparison with four PFs, one collagenized dermatofibroma, two angiofibromas, and two periungual fibromas. Immunostains for CD34, CD31, O13 (CD99), Factor XIIIa, S-100, CD68 (KP-1), and MIB-1 were carried out using a labeled streptavidin-biotin method with DAKO-automated immunostainer. Paraffin blocks of two SFs were reprocessed for electron microscopic studies. Clinical data of all patients with SF were also reviewed. RESULTS: Spindle cells and pleomorphic cells in SF and PF showed diffuse immunoreactivity for CD34 and O13 but were negative for CD31, S-100, and CD68. Spindle cells in one dermatofibroma and one angiofibroma were positive for Factor XIIIa. Proliferating index (MIB-1) was very low in all cases of SF, contradicting some previous reports. CONCLUSIONS: SF is a fibrotic lesion with cells positive for CD34 and O13. It shares a common immunoprofile with PF but is distinct from dermatofibroma and other common spindle cell lesions of skin. O13 expression in SF has not been previously described.

12E7 Antigen↗
PubMed2002

Atypical lipomatous tumor of the lip with pleomorphic lipoma-like myxoid area, clinically simulating mucocele.

Lipomatous tumor is least common in the oral cavity. We present a case of atypical lipomatous tumor arising in the lower lip of an 81-year-old male. Clinical diagnosis was mucocele. The tumor measured 12 mm in diameter with a round shape. It was solid, firm, myxomatous and translucent with a small yellowish focus in the central portion. Histologically, the tumor was a circumscribed and well-encapsulated mass with prominent myxoid matrix. The central minor portion showed a well-differentiated liposarcoma. In the myxoid area, lipoblasts and large atypical cells with dense chromatin including floret-like giant cells were seen in abundance. Atypical lipomatous tumor may be indistinguishable from pleomorphic lipoma and its distinction from the latter is based on location as well as relative abundance of floret-type giant cells and lipoblasts. According to its abundance in lipoblasts over floret-like cells, pleomorphic lipoma-like area in our case could also be a part of atypical lipomatous tumor. It may be possible to interpret myxoid change in our case as to represent a superficial counterpart of myxoid malignant fibrous histiocytoma-like change reported in the retroperitoneal lesion.

Aged↗
PubMed1998

The recurrent translocation t(5;8)(p13;q12) in pleomorphic adenomas results in upregulation of PLAG1 gene expression under control of the LIFR promoter.

We have previously shown that the PLAG1 gene on chromosome 8q12 is consistently rearranged in pleomorphic adenomas of the salivary glands with t(3;8)(p21;q12) translocations. The t(3;8) results in promoter swapping between the PLAG1 gene, which encodes a novel zinc finger protein, and the constitutively expressed gene for beta-catenin (CTNNB1), a protein with roles in cell-cell adhesion and the WG/WNT signalling pathway. In order to assess the importance of other translocation partner genes of PLAG1, and their possible relationship to CTNNB1, we have characterized a second recurrent translocation, i.e. the t(5;8)(p13;q12). This translocation leads to ectopic expression of a chimeric transcript consisting of sequences from the ubiquitously expressed gene for the leukemia inhibitory factor receptor (LIFR) and PLAG1. As for the t(3;8), the fusions occurred in the 5'-noncoding regions of both genes, exchanging regulatory control elements while preserving the coding sequences. The results of the current as well as previous studies indicate that ectopic expression of PLAG1 under the control of promoters of distinct translocation partner genes is a general pathogenetic mechanism for pleomorphic adenomas with 8q12 aberrations.

Adenoma↗
PubMed2006

Cooperation of oncogenic K-ras and p53 deficiency in pleomorphic rhabdomyosarcoma development in adult mice.

Human rhabdomyosarcomas (RMSs) frequently demonstrate genetic alterations in ras and p53. To investigate their possible involvement in the tumorigenesis, we generated a knock-in mouse line with oncogenic K-ras, conditionally expressed by Cre/LoxP system on a background of p53 alteration. Electroporation of Cre expression vector in skeletal muscle tissues resulted in the generation of tumor in adults with tumor incidences of 100% at 10 weeks and 40% at 15 weeks, in p53(-/-) and p53(-/+) backgrounds, respectively. The tumor histology was pleomorphic RMS with characteristic bizarre giant cells, positive for desmin and alpha-sarcomeric actin and exhibiting remarkable increase in total and phosphorylated extracellular signal-regulated protein kinase (ERK)1 and ERK2. Loss of the wild-type p53 was detected in K-rasG12V-expressed tumors of p53(-/+) mice. Early lesions 3 weeks after electroporation consisted of proliferating populations of myogenic progenitors, including stem cells positive for ScaI antigen, immature cells positive for desmin and neural cell adhesion molecule-positive myotubes. Thus, cooperation of oncogenic K-ras and p53 deficiency resulted in the development of pleomorphic RMS in adult mice, providing a useful mouse model for further detailed studies.

Animals↗
PubMed1997

Nuclear pleomorphism in typical carcinoid tumours of the lung: problems in frozen section interpretation.

Pulmonary typical carcinoid tumours are generally easy to diagnose with their uniform cells, carcinoid growth pattern and lack of mitoses. However, nuclear pleomorphism, which is common in other neuroendocrine tumours, is not emphasized in pulmonary carcinoid tumours. Three cases of typical carcinoid tumours, because of marked nuclear pleomorphism on frozen section, were misdiagnosed as non-small cell carcinomas.

Adult↗
PubMed1998

Fatal pleomorphic xanthoastrocytoma with meningeal gliomatosis.

AIMS: To report the previously undescribed phenomenon of extensive meningeal gliomatosis in a pleomorphic xanthoastrocytoma (PXA) and to examine possible prognostic features. CASE DETAILS: An 11-year-old girl underwent excision of a left temporoparietal pleomorphic xanthoastrocytoma and 8 months later underwent re-excision of a local tumour recurrence. Although mitoses were not present in any of the resection specimens, the development of necrosis and increased immunoreactivity for proliferating cell nuclear antigen (PCNA) indicated anaplastic transformation in the recurrent tumour. Three months later extensive meningeal gliomatosis with minimal local recurrence resulted in death. CONCLUSIONS: Subarachnoid dissemination of a locally recurrent PXA in the absence of mitotic activity is an extremely unusual occurrence. PCNA expression in the initial excision specimens did not predict subsequent anaplastic transformation.

Astrocytoma↗
PubMed2001

Pleomorphic lobular carcinoma of the breast: its cell kinetics, expression of oncogenes and tumour suppressor genes compared with invasive ductal carcinomas and classical infiltrating lobular carcinomas.

AIMS: The study addresses whether pleomorphic lobular breast carcinomas represent a distinct entity with respect to proliferation and apoptosis as well the expression of the p53, bcl-2 and Her2 protein. METHODS AND RESULTS: The study included 30 cases of pleomorphic lobular carcinoma (PLC; G2 n=15, G3 n=15). Poorly differentiated invasive ductal carcinomas (IDC; n=15) and well-differentiated infiltrating lobular carcinomas (ILC; n=15) were used as controls. Lymph node metastases were present equally in all groups. MIB-1 labelling was counted as: PLC (G2) 8.36%; PLC (G3) 11.3%; IDC 44.26%; ILC 2.19% (P=0.0001, P=0.004, P=0.001). Apoptotic index was: PLC (G2) 0.82%; PLC (G3) 1.2%; IDC 2.09%; ILC 0.6% (P=0.009, P=0.001). Over-expression of Her2 protein was detected in 53% of PLC (G3) tumours and was present only in scattered cases in the other groups. PLCs and ILCs were strongly positive for bcl-2 and for hormone receptors, while p53+ cells were rare. IDCs exhibited a heterogeneous staining pattern for bcl-2 and for hormone receptors, while p53+ cells occurred considerably more frequently. Stage could not be linked directly to proliferation or apoptosis. CONCLUSION: Our data suggest that more frequent over-expression of Her2 among PLCs (G3) as well as the generally low apoptosis can contribute to their aggressive behaviour.

Adult↗
PubMed2003

Microsatellite instability in a pleomorphic rhabdomyosarcoma in a patient with hereditary non-polyposis colorectal cancer.

AIMS: To describe the rare occurrence of a pleomorphic sarcoma with microsatellite instability in a patient with hereditary non-polyposis colorectal cancer (HNPCC). METHODS AND RESULTS: A soft tissue tumour was removed from the upper leg of a patient who had previously been shown to harbour a germ-line MSH-2 mutation. The tumour was analysed with immunohistochemistry and molecular methods. The morphology and immunohistochemical findings were in keeping with a pleomorphic rhabdomyosarcoma. Microsatellite instability was documented in the tumour with molecular methods and in addition loss of MSH-2 expression in the tumour cells was confirmed by immunohistochemistry. CONCLUSIONS: Although sarcomas do not form part of the HNPCC diagnostic criteria, they may occur in this mismatch repair syndrome and, moreover, may well be caused by the underlying genetic defect.

Adult↗
PubMed2003

Malignant peripheral nerve sheath tumor of small round cell type with pleomorphic spindle cell sarcomatous areas.

An unusual case of malignant peripheral nerve sheath tumor (MPNST) arising in the posterior mediastinum of a 59-year-old man is reported. Histopathologically, the tumor showed an admixture of a dense proliferation of small round cells resembling a primitive neuroectodermal tumor (PNET) and a pleomorphic spindle cell sarcomatous area. Abortive rosettes, primitive neural tube-like structures, and a few glandular structures were found in the small round cell area. Small round cells were immunoreactive for neural cell adhesion molecule and synaptophysin, but were not immunoreactive for MIC2 and neuron-specific enolase. Pleomorphic spindle cells were occasionally arranged in a storiform pattern and were diffusely immunoreactive for S-100 protein. The MPNST of small round cell type is distinguishable from PNET by its negative immunoreactivity for MIC2, and the present tumor is assumed to be derived from primitive neuroectodermal cells in the peripheral nerve capable of bidirectional (neuron and Schwann cell) differentiation.

Biomarkers, Tumor↗