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PubMedDate not supplied

Pleomorphic xanthoastrocytoma: report of a case with light and electron microscopy.

A case of pleomorphic xanthoastrocytoma is reported with light and electron microscopic findings. This unusual tumor arose in a 15-year-old male. The tumor consisted predominantly of nests of xanthomatous cells and plump spindle cells surrounded by a prominent reticulin network. There was considerable cellular pleomorphism with abundant bizarre giant cells and multinucleated cells. Occasional mitoses were present. Electron microscopy and immunoperoxidase localization of glial fibrillary acidic protein (GFAP) confirmed the glial nature of the tumor. Recognition of this tumor is important. Despite its "m alignant" appearance, the tumor characteristically has a relatively good prognosis and should not be confused with high-grade gliomas or meningeal sarcomas, which require aggressive therapy.

Adolescent↗
PubMedDate not supplied

Glial fibrillary acidic protein expression in pleomorphic adenoma of salivary gland: an immunoelectron microscopic study.

Previous immunocytochemical studies of pleomorphic adenomas have demonstrated consistent labeling with glial fibrillary acidic protein (GFAP). Cross-reactivity with other intermediate filaments of similar structure and chemical composition has been suggested to account for this seemingly inappropriate pattern of immunoreactivity. To investigate further this phenomenon, we examined five pleomorphic adenomas by immunoelectron microscopy. Ultrastructural features were similar to those described by other investigators, with ductal epithelium being surrounded by myoepithelial cells and modified cells becoming detached to form the isolated stellate and spindle cells of the stroma. As part of this process, many neoplastic myoepithelial cells appeared to lose their specialized ultrastructural features, assuming a rather undifferentiated appearance. Single and double immunoelectron microscopic labeling showed vimentin filaments in all these neoplastic myoepithelial cells. In contrast, GFAP filaments were identified only in the most undifferentiated cells. Such restriction of GFAP filaments to an ultrastructurally definable subset of neoplastic cells provides strong evidence against nonspecific staining due to cross-reactivity. Given the previously described coexpression of vimentin and GFAP by neoplastic cartilage, it appears likely that this immunophenotype in neoplastic myoepithelial cells reflects early chondroid differentiation.

Adenoma↗
PubMedDate not supplied

Pleomorphic xanthoastrocytoma: a report of two cases.

We report two cases of a recently isolated variety of astrocytoma, pleomorphic xanthoastrocytoma, affecting the cerebral cortex and meninges of children and young adults. The first tumor was localized in the left frontal lobe of a 9-year-old girl. The second appeared in the right parietal lobe of a 14-year-old girl. Both tumors displayed a pleomorphic cellular proliferation, with spindle-shaped and bizarre multinucleated giant cells, some positive for neutral lipids, with a prominent reticulin network and areas highly suggestive of malignant fibrohistiocytomas (fibroxanthosarcomas). The glial fibrillary acidic protein was demonstrated by the immunoperoxidase method in the cytoplasm of the giant and the spindle cells. Ultrastructural studies confirmed the glial nature of the tumor. This type of tumor seems to carry a much better prognosis than other tumors from which it has to be separated, e.g., glioblastoma and meningeal sarcomas.

Adolescent↗
PubMedDate not supplied

Pleomorphic adenoma (benign mixed tumor) of the trachea.

A 15-year-old "asthmatic" found to have a pleomorphic adenoma of the trachea was treated by staged CO2 laser excision. Primary tracheal tumors, the clinicopathologic features of mixed tumor in this rare location, and therapeutic options are briefly reviewed. Immunohistochemical stains for cytokeratin, S-100 protein, and glial fibrillary acidic protein are reliable methods of evaluating component cell types in pleomorphic adenoma, but immunohistochemical evidence has not resolved the issue of tumor histogenesis.

Adolescent↗
PubMed1985

Pleomorphic xanthoastrocytoma with 18-year survival. Case report.

The authors present a case of right parietal pleomorphic xanthoastrocytoma that occurred in a 24-year-old man. The patient was originally operated on in 1966, and at that time the diagnosis of monstrocellular sarcoma was made. The patient is still alive and totally symptom-free. A careful reevaluation of the microscopic findings, including positive glial fibrillary acidic protein staining, led to the definite diagnosis of pleomorphic xanthoastrocytoma.

Adult↗
PubMed2000

Pleomorphic hyalinizing angiectatic tumor of soft parts: immunohistochemical study including the expression of vascular endothelial growth factor.

We report morphologic, flow cytometric, and immunohistochemical findings in two cases of pleomorphic hyalinizing angiectatic tumor of soft parts. Both patients were middle-aged women with subcutaneous lesions located in the lower extremity. The tumors consisted of sheets of spindled and pleomorphic cells with frequent intranuclear pseudoinclusions associated with clusters of ectatic vessels surrounded by prominent perivascular hyaline material. Numerous, nonhyalinized vessels were also present, mostly in the peripheral areas of the lesions. Some of these vessels had their walls permeated by numerous small capillaries. Immunostaining for vascular endothelial growth factor (VEGF), a secreted protein that has been implicated in tumor-associated angiogenesis, demonstrated positive staining in both tumoral and endothelial cells. Tumor cells were also reactive to vimentin and CD34. Focal positivity for CD99 and factor XIIIa was also present. Flow cytometry yielded a diploid DNA histogram with S-phase fraction of 7%. Our findings corroborate those from previously reported cases. They further suggest that angiogenesis and the angiogenic factor VEGF may play a role in the development of this peculiar tumor.

12E7 Antigen↗
PubMed2001

Pigmented pleomorphic xanthoastrocytoma: report of a rare case with review of the literature.

We describe a rare case of melanotic pleomorphic xanthoastrocytoma in a 32-year-old man who presented with partial complex seizures. Radiologically, the mass was located in the medial temporal lobe and was solid and cystic. Microscopic examination revealed features of a pleomorphic xanthoastrocytoma with some heavily pigmented cells. The pigment was demonstrated to be melanosomal melanin, which was confirmed by special stains, immunohistochemistry, and electron microscopy.

Adult↗
PubMed2003

Pleomorphic leiomyosarcoma of the adrenal gland.

Primary leiomyosarcomas arising in the adrenal gland are exceedingly rare, with only 3 cases reported in the literature. We present the clinical, morphologic, and immunohistochemical features of a pleomorphic leiomyosarcoma, a variant of leiomyosarcoma that has not been described in the adrenal gland. A 63-year-old man presented with a 1-year history of enlarging right upper quadrant mass and pulmonary nodule. A diagnosis of metastatic pulmonary carcinoma to the adrenal gland was rendered on a needle biopsy specimen. Preoperative chemotherapy reduced only the pulmonary mass but not the adrenal mass, which continued to enlarge. Documented by computed tomography and confirmed at surgery, the tumor had completely replaced the right adrenal gland, invading into both the posterior aspect of the right liver and the superior pole of the right kidney. Histologic sections showed a diffuse proliferation of pleomorphic, large, and polygonal neoplastic cells with prominent nucleoli. Many bizarre mitotic figures were present. The neoplastic cells were strongly positive for desmin, calponin, and vimentin. Approximately 80% of the neoplastic cells were positive for the proliferation marker Ki-67. They were negative for smooth muscle actin, muscle-specific actin, myoglobin, myogenin, CD117, cytokeratins, carcinoembryonic antigen, epithelial membrane antigen, chromogranin, CD34, CD31, S100 protein, and HMB-45.

Adrenal Gland Neoplasms↗
PubMed1999

Pleomorphic hyalinized angiectatic tumor of soft parts.

Pleomorphic hyalinized angiectatic tumor of soft parts is a recently described neoplasm that most commonly affects the lower extremities. It is locally aggressive but has not been known to metastasize. This article presents a case of a softball-sized tumor on the dorsum of the foot that was identified as pleomorphic hyalinized angiectatic tumor of soft parts. Previously, it would have been misdiagnosed and treated as either a neurilemoma or a malignant fibrous histiocytoma.

Adult↗
PubMed1999

[Posterior mediastinal diffuse pleomorphic lymphoma].

A 26-year-old man presented with a 38 degrees C fever of undetermined origin in November 1977. His fever subsided in 1 month, but recurred concomitantly with dysphagia on December 10. For this reason, the patient visited our out patient clinic on December 15, and was hospitalized because a mass was found radiographically in the left lower lung field. A contrast-enhanced computed tomographic scan of the chest revealed an irregularly-shaped mass encircling the esophagus. Based on open-lung biopsy findings, the mass was diagnosed as non-Hodgkin's lymphoma, diffuse pleomorphic type. Neither swelling of the superficial lymph nodes nor hepatosplenomegaly was detected, and a bone-marrow aspiration specimen disclosed no atypical cells. Ga scintigraphy found accumulation only in this region, suggesting the posterior mediastinum as the origin of the lymphoma. Reports of non-Hodgkin's primary lymphoma in the posterior mediastinum are rare. Further, to our knowledge, there have been no reports at all on the diffuse pleomorphic type to date. This case was accordingly considered to be of highly informative value.

Adult↗
PubMed1999

Pleomorphic xanthoastrocytoma: what do we really know about it?

BACKGROUND: Pleomorphic xanthoastrocytomas (PXA) may recur and demonstrate aggressive clinical behavior with a mortality rate between 15% and 20%. To the authors' knowledge, no histopathologic features currently are known to reliably predict recurrence or tumor progression. METHODS: The study was based on 71 cases with available information regarding clinical and therapeutic data and follow-up. Diagnostic features included cellular pleomorphism, giant and/or xanthic cells, eosinophilic granular bodies, desmoplasia, and leptomeningeal involvement. The mitotic index (MI), the presence of necrosis, and endothelial proliferation were recorded in all primary resection specimens. RESULTS: The study included 35 females and 36 males, age 26+/-16 years (mean +/- standard deviation). Approximately 98% of tumors were supratentorial, with 49% in the temporal lobe. Seizures were the presenting symptoms in 71% of patients. Extent of tumor removal was macroscopic total resection in 68% of cases and subtotal resection (STR) in 32% of cases. Postoperative radiotherapy, alone or with chemotherapy, was administered in 29% and 12.5% of cases, respectively. The recurrence free survival rates (RFS) were 72% at 5 years and 61% at 10 years, whereas overall survivals rates (OS) were 81% at 5 years and 70% at 10 years. In univariate analysis, the extent of resection was the single factor associated most strongly with RFS (P=0.003), followed by MI (P=0.007) and atypical mitoses (P=0.04). Necrosis was not found to be significant. The extent of resection and MI were confirmed as independent predictors of RFS by multivariate analysis. MI (P=0.001), atypical mitoses (P=0.02), and necrosis (P=0.04) were associated with OS by univariate analysis. In multivariate analysis, only MI was an independent predictor of survival. Information regarding MIB-1 labeling index and the use of adjuvant therapy was too limited to explore their prognostic significance confidently. CONCLUSIONS: The study confirms that PXA is an astrocytic tumor with a relatively favorable prognosis. MI and extent of resection appear to be the main predictors of RFS and OS. Given the slow growth of the tumor, more studied cases and longer periods of follow-up will be essential to confirm our findings regarding prognostic factors affecting this unusual tumor.

Adolescent↗
PubMed1999

Epithelioid variant of pleomorphic liposarcoma: a study of 12 cases of a distinctive variant of high-grade liposarcoma.

We describe 12 patients with a distinctive variant of pleomorphic liposarcoma that histologically shows epithelioid features and focally resembles a solid carcinoma. The tumors occurred in nine men and three women (median age, 63 yr; range, 40-78 yr). Five tumors were in the thigh, two in the chest wall, two in the axilla, and one each in the retroperitoneum, groin, and calf. Most were 15 to 20 cm in maximal diameter. They consisted of sheets of epithelioid-appearing cells with ample, variably eosinophilic cytoplasm, often showing a honeycomb-like pattern of cell borders and little if any collagenous extracellular matrix. Their histologic features often resembled those of renal clear cell carcinoma or adrenal cortical carcinoma, but all showed evidence of adipocytic differentiation, and five also showed focal spindle cell components. One patient whose tumor in the thigh had been originally diagnosed as metastatic renal carcinoma had undergone nephrectomy without a finding of a kidney tumor. All of the cases were positive for vimentin; 6 of 11 cases were positive for S-100 protein, usually focally; 5 of 11 were focally positive for keratins; and all were negative for epithelial membrane antigen, muscle actins, desmin, and CD34. High mitotic activity (mean, 42 mitotic figures per 10 high power fields) and high MIB-1-positive proliferative fraction (>30%) were seen in all of the cases, and nuclear p53 immunoreactivity was detected in five of seven cases. Of the eight patients with complete follow-up, five died of disease (median survival, 6 mo), two died of unrelated causes 10 and 18 years later, and 1 was alive and well 24 years later. The epithelioid variant of pleomorphic liposarcoma is a high-grade tumor that must be distinguished from malignant epithelial tumors, especially in view of the keratin immunoreactivity of some of these neoplasms.

Adult↗
PubMedDate not supplied

Pleomorphic T-cell lymphoma with chondropathia tuberosa; a case report and review.

Pleomorphic T-cell-lymphoma (anaplastic IgA-plasma cell tumor) belongs to the group of malignant non-Hodgkin's lymphomas (NHL). The histological and immunophenotypical subtypes differ with genetic and environmental etiologic factors. Lymphomas arise from the clonal proliferation of precursor cells within lymphoid organs with acquired chromosomal abnormalities. Approximately 5% of all primary malignant bone tumors are NHL, the majority of diffuse large B-cell type. Our case history can be regarded as the first published in English language reporting on a pleomorphic T-cell-lymphoma imitating a Chondropathia tuberosa (Tietze's syndrome): The tumor appeared with a tender tumescence over the sternum and a painful swollen left sterno-clavicular joint--as a rule a typical sign for Tietze's syndrome. Only sternal puncture followed by immune histology confirmed an anaplastic IgA-plasma cell tumor. The primary tumor, and later on an osteolysis of cervical vertebrae I-III with a complete destruction of the axis and an affection of the dens atlantis could not be detected by radiographic examinations. Moreover, this tumor infestation could only be depicted by the magnet resonance imaging and the computed tomography. Furthermore, other results of our report are the very rare manifestation of a T-cell lymphoma as a pedicled tumor near the pancreas or of pancreatic origin and the excellent result of an autologous stem cell transplantation. Reviewing the literature, we want to discuss the present scientific and clinical standards of diagnosis, progress and treatment of Chondropathia tuberosa and T-cell lymphoma, and we want to point out some new aspects of both diseases.

Adult↗
PubMed2000

[Atypical meningioma: morphometric analysis of nuclear pleomorphism].

The revised edition of the WHO classification of brain tumours now includes the "atypical" meningioma (grade II) which should be placed between the common type (grade I) and anaplastic type (grade III) according to histomorphological features and prognosis. However, diagnostic criteria for atypical meningioma are vague and the significance of brain invasion in the determination of malignancy is controversial. Nuclear pleomorphism and mitoses are usually considered the most important parameters to distinguish atypical and malignant meningiomas. According to WHO classification we selected eight cases of meningioma diagnosed as atypical (3 cases) and malignant (5 cases). All the tumours were supratentorially located. Nine cases of benign meningiomas were also studied as a control group. Morphometrical analysis was carried out by S.A.M. (Shape Analytical Morphometry) system. S.A.M. logical architecture assumes that each irregular shape contains elements of two distinct logical domains: gross distortions that interest the contour and its local perturbations. These features were investigated separately by analytical procedures to acquire independent parameters both on the logical and the numerical level. The results, statistically evaluated, show that nuclear pleomorphism is not a satisfactory criterion, if used alone, to distinguish atypical from malignant meningioma (Discriminant Analysis: 19% of minimum error).

Brain Neoplasms↗
PubMedDate not supplied

Pleomorphic adenoma of the nasal septum: MR features.

We report the MR imaging features of a pleomorphic adenoma of the nasal septum. To our knowledge, whereas the CT findings of pleomorphic adenomas of the nasal septum have been reported, the MR features of this rare entity have not been reported in the English-language literature.

Adult↗
PubMed2000

Pleomorphic xanthoastrocytoma--a clinicopathological study.

Six cases of Pleomorphic Xanthoastrocytoma of central nervous system are presented. One case presented with recurrent refractory seizures and others as intracranial space occupying lesions. They were located in temporal/parietal lobes, were partly cystic and partly solid on CT scan, enhancing with contrast. Histopathology was characterized by pleomorphic giant cells and cells with vacuolated cytoplasm. Glial fibrillary acidic protein was strongly positive in all the cases.

Adolescent↗
PubMed1975

Pleomorphic Rhabdomyosarcoma: response to irradiation.

Although the usefulness of radiation in treatment of many embryonal rhabdomyosarcomas is recognized, the pleomorphic rhabdomyosarcomas are frequently felt to be radioresistant and thus a potentially useful mode of therapy is overlooked. There is increasing evidence in the literature to document successful local management of pleomorphic rhabdomyosarcomas with radiation. The literature is reviewed briefly and a case of rhabdomyosarcoma of the heart is reported in which radiation in doses well tolerated by normal tissues successfully controlled several local lesions at various sites until the patient's demise from widespread disease 2 years after the initial treatment.

Aged↗
PubMed2001

Pleomorphic liposarcoma.

Pleomorphic liposarcoma (PLS) is defined as a high-grade pleomorphic sarcoma containing multivacuolated lipoblasts. PLS arises most frequently in the extremities of older individuals and often metastasizes to the lungs. The prognosis of PLS parallels that of many other high-grade sarcomas. In a small analysis combining clinicopathologic data available from 16 previously reported and 8 additional cases of PLS arising in the extremities, the 5-year overall survival rate for the 24 patients was 40% (median survival, 48 months). By univariate analysis, patients with tumors located in the upper extremities (P = .021) and greater than 10 cm (P = .047) had decreased overall survival. Older age, female sex, epithelioid phenotype, and radiotherapy or chemotherapy administration were not significantly associated with an adverse outcome.

Adult↗