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PubMed1986

Pleomorphic lipoma of the tongue: case report and literature review.

A case of pleomorphic lipoma of the tongue in a 60-year-old woman is reported. Recently described by Enzinger (1977), pleomorphic lipoma is a rare benign tumor, occurring mostly in elderly males. The subcutaneous tissues of the neck and back are the most common sites involved. Differentiation from some histological variants of liposarcoma remains difficult. Complete surgical excision is the treatment of choice. To our knowledge, this is the first case of pleomorphic lipoma of the tongue reported in the English literature.

Female↗
PubMed1986

[Histogenesis of benign pleomorphic mesenchymal tumors].

Benign pleomorphic mesenchymal tumours (lipoma, fibroblastoma) are defined by large cells which have multiple peripheral nuclei and thus remind of a flower. Similar cells were already previously detected by Mirejovský as a reactive change in polypous processes. We assume that these cells may occur not only in non-tumours but also in tumours where similar stromal conditions exist as in polyps. Therefore pleomorphic giant cells are of no value for assessment of the histogenesis of tumours. Nevertheless giant cell pleomorphic reactive changes may be mistaken for atypical tumours and therefore their knowledge is of practical importance.

Fibroma↗
PubMed1985

[Pleomorphic xanthoastrocytoma (Kepes): a case report].

A case of tumor to be diagnosed as pleomorphic xanthoastrocytoma (Kepes) is reported. This patient was a 34-year-old female with a 6-year history of TIA. Neurological examination on admission showed no abnormalities except for bilateral choked disc. Plain CT scan revealed a well-defined low density area with a small high density region in the right temporal lobe. The small high density region and a part of peripheral portion of low density area were moderately enhanced with contrast media. At operation there was a cyst containing xanthochromic fluid at 1.5 cm depth from the cerebral surface. Temporal lobectomy and subtotal removal of tumor (5gr) were performed. The patient received postoperative radiation therapy (5960 rad). She has been doing extremely well for these 5 years following craniotomy and has no deficits except for the left upper quadrant hemianopsia which appeared immediately after surgery. There cannot be observed any symptoms or signs suggesting tumor recurrence. Histologically the tumor cells displayed marked pleomorphism. However, either necrosis or mitosis were very hard to find. The tumor cells were surrounded by a dense network of reticulin fibers. Electron-microscopically the tumor cells were occasionally filled with glial fibrils, and lipid granules were seen. Immunoperoxidase technique revealed both glial fibrillary acidic protein (GFAP) and S-100 protein in the cytoplasm of tumor cells, suggesting of neuroectodermal origin. Although this patient is older than previously reported cases (age 3 to 32), the histological findings as well as the good postoperative course indicate that this case may fulfill the criteria of pleomorphic xanthoastrocytoma first proposed by Kepes et al.

Adult↗
PubMed1984

The pleomorphic cells of advanced mycosis fungoides. An ultrastructural study.

Five patients with advanced disseminated mycosis fungoides were studied, using light and electron microscopy. All had lesions with large pleomorphic cells by light microscopy. In three of the patients, nonlymphoid tissue was studied, including pericardium, epididymis, and small intestine. All areas selected for ultrastructural study showed large pleomorphic cells. We conclude that these represent poorly differentiated lymphoid cells derived from Sézary lymphocytes. This is based on nuclear and organelle similarities between the Sézary and pleomorphic cells, as well as the demonstration of intermediate forms.

Cell Nucleus↗
PubMedDate not supplied

Cytopathology, including transmission and scanning electron microscopy, of pleomorphic liposarcomas in pleural fluids.

Liposarcoma cells in pleural fluid from two patients with metastatic pleomorphic liposarcoma are described. The major diagnostic feature of such specimens, perceivable by light microscopy, is the presence of solitary, pleomorphic giant cells with cytoplasmic vacuoles. In some cells, transmission electron microscopy revealed numerous cytoplasmic lipidic droplets. With scanning electron microscopy, the cellular surfaces were markedly pleomorphic, with ruffles, blebs and long, thin processes.

Adult↗
PubMed1981

The use of optical Fourier transforms to diagnose pleomorphism, size and chromatin clumping in nuclear models.

Nuclear features of size, pleomorphism and chromatin clumping are distinctive and quantifiable in the optical Fourier transform of the nucleus. This is shown in photographs of models, tracings and hematoxylin-stained impression smears of various types of nuclei. The size of the transform is inversely proportional to the size of the nucleus. Irregularities in shape (pleomorphism) produce radially symmetric rays of light in the transform. The effect of chromatin clumping is to give a mottled pattern superimposed on the pleomorphism pattern. The transform features can be measured in real time using a ring-wedge or similar detector. These procedures might be used for both automatic screening and objective quantification of diagnoses.

Cell Nucleus↗
PubMed1995

Pleomorphic lipoma in the middle mediastinum.

Mediastinal pleomorphic lipoma was found in a 63-year-old Thai male who presented with problems of chronic cough, dyspnea and dysphagia for 1 year. CT and MRI studies revealed a well-circumscribed mass in the middle mediastinum. Thoracotomy was performed and excision of the tumor was done completely. The pathological features of the tumor were typical of pleomorphic lipoma. While lipomas are common tumors in the mediastinum, liposarcomas are rare and there has been no reported case of mediastinal pleomorphic lipoma before. Differential diagnosis of liposarcoma was very important in this case due to different clinical courses and prognoses.

Humans↗
PubMedDate not supplied

Pleomorphic xanthoastrocytoma: report of two cases and brief review of the literature.

Two cases of pleomorphic xanthoastrocytoma (PXA) involving the temporal lobe are reported, both occurring in adolescents. This neoplasma is a recently described, rare variant of astrocytoma affecting the superficial cerebral cortex and meninges of children and young adults. The tumor is considered to arise from the subpial astrocytes of the superficial cortex. Electron microscopic examination and immunoperoxidase stains for glial fibrillary acidic protein (GFAP) are helpful in making a definitive histologic diagnosis. Despite its pleomorphic appearance, this type of supratentorial glioma appears to have a much better prognosis than other tumors from which it must be distinguished, such as high grade gliomas and meningeal sarcomas. In contrast to malignant gliomas, the pleomorphic xanthoastrocytoma does not appear to require aggressive postoperative radiation therapy or chemotherapy. Therefore, it is important to recognize and identify this type of glioma as a distinct entity.

Adolescent↗
PubMed1997

Mesenteric pleomorphic liposarcoma in an adolescent.

We report a case of pleomorphic liposarcoma arising in the root of the mesentery of an adolescent girl. Pleomorphic liposarcoma is an extremely rare tumor in the pediatric age group, and few well-documented cases are found in the literature. To the best of our knowledge, none have been described in the abdomen. The histologic and ultra-structural features of this tumor are described, and the literature concerning pediatric pleomorphic liposarcoma is reviewed.

Adolescent↗
PubMed1997

[Pleomorphic hyalinizing angiectasic soft-tissue tumor. Description of a case].

INTRODUCTION: Pleomorphic hyalinizing angiectasic tumor of soft parts is a recently described tumor of adults showing low malignant potential. MATERIAL AND METHODS: We describe the case of a 80 yr-old woman with a palpable mass located in the subcutis of the right popliteal fossa. Tissue was formalin-fixed and processed as routine. Sections were stained with Hematoxylin-Eosin. In addition, the lesion was studied with histochemical stainings for mucins and immunocytochemistry. RESULTS: The lesion was well-circumscribed by a fibrous pseudocapsule and was composed mostly by short strands of spindle cells with pleomorphic nuclei and several vessels surrounded by hyalinized material. Necrosis and mitoses were absent. Neoplastic cells immunoreacted with anti-Qbend antiserum (CD34). DISCUSSION: Pleomorphic hyalinizing angiectatic tumor of soft parts was distinguished from solitary fibrous tumor. A common origin of these lesions is proposed.

Aged↗
PubMed1984

Recurrent pleomorphic adenomas of the parotid gland.

In this retrospective study of 19 cases of recurrent pleomorphic adenoma of the parotid gland, all 19 patients underwent primary surgery elsewhere, namely, lumpectomy in five cases and superficial parotidectomy in 14 cases. The age at which those patients with recurrence had originally been seen was significantly earlier than those seen in our series of cases of primary surgery for pleomorphic adenoma. If the primary operation had been a parotidectomy, the average time interval between the first and second operation was 7.7 years; however, if it had been a lumpectomy, it was ten months. Implantability of the tumor and inadequate surgery were reasons for tumor recurrence. The suggested treatment of recurrence is total parotidectomy with preservation of the facial nerve. Revision surgery has been successful in all cases with no further recurrences, except in two cases in which multiple operations had already been performed.

Adenoma, Pleomorphic↗
PubMed1984

Carcinomas ex pleomorphic adenoma and malignant mixed tumors. Histomorphologic indexes.

Clinical and pathologic differences exist between the several neoplasms encompassed by the term malignant mixed tumors of salivary glands. The majority of the neoplasms are carcinomas ex pleomorphic adenoma. True malignant mixed tumors (carcinosarcomas) are rare, and even more rare are the benign metastasizing mixed tumors. This study of 40 malignant mixed tumors indicates that two previously unreported variables, measured invasion in millimeters and histologic subclassifications of the malignant neoplasm, are valuable guides to prognosis and biologic behavior. All patients whose malignant neoplasm extended for more than 8 mm beyond residual capsule or benign residual tumor died of their disease. The extent of invasion also correlated with perineurial invasion, involvement of bone, and metastases to lymph nodes. Histologic subclassification points out that there is no prototypical carcinoma ex pleomorphic adenoma and that high- and low-grade carcinomas can be found. Only one of the patients with low-grade (terminal duct) carcinomas died of his disease during follow-up periods extending to over 20 years.

Adenoma, Pleomorphic↗
PubMed1986

Human pleomorphic adenomas transplanted to nude mice.

Tissue from 13 human pleomorphic adenomas was transplanted to a total of 64 nude mice. Eight of the tumors were transplanted into a second passage of mice, 17 in all. In 39 mice of first passage, there was a definite increase in graft size. Microscopic examination showed no change in the histologic pattern from the donor tumor to the transplanted tissue. The heterochromatin pattern after staining with the DNA-specific fluorochrome D287/170 allowed distinction between human and murine cells and showed that both epithelial and mesenchymal cells were of human derivation. Autoradiographic studies with tritiated thymidine showed that both epithelial and mesenchymal tumor cells were labeled. Our results thus show that cell proliferation in the human pleomorphic adenoma takes place in epithelial areas as well as in mesenchymal areas.

Adenoma, Pleomorphic↗
PubMed1986

Surgical treatment of recurrent pleomorphic adenoma of the parotid gland.

Recurrent pleomorphic adenomas of the parotid gland warrant consideration because of the potential for facial nerve injury occurring with surgical treatment and the risk of malignant conversion. Forty-eight cases of recurrent pleomorphic adenoma treated at the University of Michigan, Ann Arbor, between 1935 and 1975 were retrospectively analyzed. The results of surgical procedures for recurrence were determined with respect to tumor control and resultant facial nerve function. Malignant conversion developed in three (6%) of 48 cases. The results of this study underscore the importance of adequate surgical excision of initial recurrences as well as primary tumors to prevent tumor recidivism. Tumor control rates and facial nerve preservation are enhanced with formal parotidectomy for recurrent tumor when feasible. In cases in which facial nerve identification and dissection is not possible, en bloc total parotidectomy offers effective, though not absolute, control of extensive recurrence.

Adenoma, Pleomorphic↗
PubMed1998

Recurrent primary pleomorphic adenomas of salivary gland origin: intrasurgical rupture, histopathologic features, and pseudopodia.

BACKGROUND: The rate of tumor recurrence after surgery for benign salivary gland pleomorphic adenoma varies considerably in different clinical settings and seems to depend to a great extent on the surgical technique used. The importance of tumor spillage for subsequent recurrence has recently been questioned. The current follow-up study was undertaken to ascertain whether intrasurgical rupture, tumor spillage, or any histopathologic feature might have had an impact on the rate of recurrence. METHODS: The medical records of all 255 patients operated on for benign salivary gland pleomorphic adenoma between the years 1974 and 1993 at the Department of Otorhinolaryngology, Huddinge University Hospital, were reviewed. All patients alive in April 1995 (n = 230) were sent a simple questionnaire. Two hundred thirteen of these patients received follow-up. All cases of tumor recurrence after surgery or intrasurgical rupture of the tumor capsule were reviewed histopathologically. RESULTS: Two (7.1%) of the 28 patients who had macroscopic capsule rupture during surgery experienced recurrence at a later stage. This was not a statistically higher rate than the 4.1% recurrence rate for the rest of the material. As many as 5 of the 9 primary tumors that subsequently recurred (56%) sent fingerlike tumor extensions or pseudopodia outside the pseudocapsule. The rate of occurrence of such structures was statistically higher than that of the tumors that ruptured during surgery (25%) and the examined uncomplicated cases (8%). CONCLUSIONS: Occurrence of pseudopodia--microscopic fingerlike formations of tumor tissue that extend beyond the main lump of the tumor--is a significant risk factor for local recurrence.

Adenoma, Pleomorphic↗
PubMed1996

Fine-needle sampling of salivary gland lesions. I. Cytology and histology correlation of 412 cases of pleomorphic adenoma.

Fine-needle sampling (FNS) of 412 pleomorphic adenomas, corresponding to 378 primary tumors and 34 local recurrences, was performed preoperatively in 378 patients. Concordant cytologic diagnoses were established in 376 tumors (91.3%), whereas seven (1.7%) were only classified as benign. Sixteen (3.9%) tumors were considered to be suspicious and two (0.5%) were diagnosed as adenoid cystic carcinomas. Insufficient material for cytologic evaluation was found in 11 (2.6%) tumors. Pleomorphic adenomas were retrospectively classified according to the predominant histological differentiation: chondromyxoid, cellular, myoepithelial, or metaplastic. FNS performances were higher in chondromyxoid than in other types, with 95.2% concordant and 1.4% suspicious/ false-positive, vs. 81.8% concordant, and 11.5% suspicious/false-positive cytodiagnoses, respectively.

Adenoma, Pleomorphic↗
PubMed1998

Salivary duct carcinoma ex pleomorphic adenoma: analysis of the findings in fine-needle aspiration cytology and histology.

Salivary duct carcinoma (SDC) is an uncommon and highly aggressive neoplasm that reveals histopathologic features resembling infiltrating duct carcinoma of the breast and prostate. SDC arising on the basis of preexisting pleomorphic adenoma (PA) is very rare. This report describes the fine-needle aspiration (FNA) cytology of a case of SDC ex PA. FNA smears were cellular with cells with large, pleomorphic nuclei, some prominent nucleoli, and finely vacuolated cytoplasm. The neoplastic cells were forming groups, sheets, and papillary structures and a cribriform pattern was present in some sheets. Mitotic figures were frequently seen. Necrosis was prominent in the background. Histologic sections of the tumor revealed areas of comedo carcinoma, papillary carcinoma, and infiltrative carcinoma as well as multiple foci of PA. The presence of a cribriform pattern, tumor cells resembling breast ductal carcinoma cells, and a necrotic background are helpful features for an accurate cytodiagnosis of SDC.

Adenocarcinoma↗
PubMed1996

Identification of a yeast artificial chromosome spanning the 8q12 translocation breakpoint in pleomorphic adenomas with t(3;8)(p21;q12).

A subgroup of pleomorphic adenomas of the salivary glands is characterized by translocations involving chromosome 8, with consistent breakpoints at 8q12. As part of a positional cloning effort to isolate the gene(s) affected by these translocations we now report the mapping of the 8q12 breakpoint in two primary pleomorphic adenomas with the recurrent t(3;8)(p21;q12). Yeast artificial chromosome (YAC) clones corresponding to eight different loci in 8q11-12 were isolated and mapped by fluorescence in situ hybridization (FISH). The t(3;8) breakpoint was mapped within a 1 Mb region flanked by MOS proximally and by the genetic marker D8S166 distally. One YAC within this region was shown to span the t(3;8) breakpoint in two tumors. This YAC will provide an excellent tool for isolating the gene(s) at the breakpoint(s) in adenomas with t(3;8).

Adenoma, Pleomorphic↗