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PubMed2004

Expression and localization of cartilage-specific matrix protein chondromodulin-I mRNA in salivary pleomorphic adenomas.

Pleomorphic adenoma is the most common epithelial tumor in the salivary glands. This tumor frequently exhibits "mesenchyme"-like components, including myxoid or chondroid areas. Recently, using immunohistochemical techniques, we reported that cartilage-specific matrix protein, chondromodulin-I (ChM-I), was deposited on the inter-territorial matrix of the chondroid area in salivary pleomorphic adenomas and that ChM-I, which is also a strong angio-inhibitory factor, plays an important role in the avascular nature of the chondroid area and the chondroid formation in this type of tumor. To elucidate which cells express ChM-I mRNA in pleomorphic adenomas, we examined the expression and localization of ChM-I mRNA in this type of tumor using an in situ hybridization technique. Immunoreactivity for ChM-I was observed in the inter-territorial matrix of the chondroid area, especially around the lacunae, and in the cytoplasm of neoplastic myoepithelial cells of the myxoid element of pleomorphic adenomas. On in situ hybridization analysis, strong signals for ChM-I mRNA were detected in the cytoplasm of the lacuna cells of the chondroid element, and moderate to marked signals were observed in the cytoplasm of the neoplastic myoepithelial cells of the myxoid element. Signals for ChM-I mRNA were also seen in the cytoplasm of the spindle-shaped neoplastic myoepithelial cells in the transitional areas between the myxoid and chondroid elements of this tumor. Signals for ChM-I mRNA were not seen in the inner ductal cells or the fibrous element. These findings indicate that lacuna cells and neoplastic myoepithelial cells express ChM-I mRNA and that mature ChM-I, which lacuna cells and neoplastic myoepithelial cells translate, is deposited in the chondroid matrix of pleomorphic adenomas. In conclusion, lacuna cells and neoplastic myoepithelial cells express ChM-I mRNA ectopically in pleomorphic adenoma, and this plays an important role in chondroid formation and hypovascularity in this type of tumor.

Adenoma, Pleomorphic↗
PubMed1998

Expression of bone morphogenetic proteins in salivary pleomorphic adenomas.

Salivary pleomorphic adenomas are often associated with chondroid tissue formation. We investigated the relationship between chondroid tissue formation and the expression of bone morphogenetic proteins (BMPs), which are strong inducers of ectopic bone and cartilage formation. Fifteen pleomorphic adenomas and seven normal salivary glands were examined genetically and immunohistochemically. Semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that BMP-1, BMP-2, BMP-3, BMP-4, and BMP-7 mRNAs were overexpressed in 10 (66.7%), 9 (60.0%), 1 (6.7%), 8 (53.3%), and 12 (80.0%), respectively, of the 15 pleomorphic adenomas. Overexpression of BMP-2 mRNA was observed in pleomorphic adenomas. Marked chondroid formation or expression of type II collagen was frequently observed in pleomorphic adenomas that overexpressed BMP-2 mRNA. Immunohistochemically, BMP-2 was detected in modified myoepithelial cells aroud chondroid tissue and basement membranes. These results suggest that BMPs, and expecially BMP-2, have a role in chondroid formation in pleomorphic adenomas.

Adenoma, Pleomorphic↗
PubMed2004

[Pleomorphic adenoma of the parotid: histopathological study].

OBJECTIVES: Capsular ruptures play a major role in recurrences of parotid pleomorphic adenomas. The aim of this retrospective study was to define histomorphological characteristics of pleomorphic adenoma in order to define possible recurrence mechanisms and to set a clear surgical management. MATERIAL AND METHOD: Histological study was performed after reviewing of slides originating from 100 patients with pleomorphic adenomas of the parotid gland. These patients were treated in our institution during the period May 1992 - November 2002. RESULTS: The studied population was distributed into 3 histological subtypes for better analysis. Hypocellular (stroma rich) pleomorphic adenoma was reported in 56%, hypercellular pleomorphic adenoma was reported in 29% and "classic" in 15%. Thinness of capsule was significantly related to hypocellularity. Pseudopodias and satellite nodules were reported in 72% of this series. CONCLUSION: Due to capsular characteristics, surgical excision should avoid dissection in the vicinity of the tumor in order to avoid capsular bare area, so minimizing the risk of surgical induced recurrence. According to these findings, enucleation surgery for pleomorphic adenoma should not be performed anymore. Parotidectomy techniques (total or lateral) constitute the surgical procedures of choice.

Adenoma, Pleomorphic↗
PubMed1999

Expression of bone matrix proteins, osteonectin and osteopontin, in salivary pleomorphic adenomas.

Osteonectin (OSN) is a glycoprotein involved in the early steps of the mineralization of skeletal tissue, while osteopontin (OPN) is a protein involved in normal and pathological calcifications. OSN and OPN are non-collageneous bone matrix proteins expressed by some epithelial tumor cells in exceptional cases. We immunohistochemically investigated the presence and the distribution of OSN and OPN in 43 pleomorphic adenomas to elucidate the production of their molecules by modified myoepithelial cells. In normal salivary glands, OSN was immunolocalized in the striated ducts, while OPN was not expressed. In pleomorphic adenomas, the inner layer of tubulo-glandular structures and modified myoepithelial cells in the myxoid areas showed moderate positivity for OSN (83.7%). OSN was expressed in all of the lacuna cells in the chondroid areas. OPN was strongly expressed in the stroma of the myxoid and hyaline areas of the pleomorphic adenomas (65.1%), but there was no expression of OPN in the chondroid area. All cases of pleomorphic adenomas expressed type IV collagen. These findings suggested that OSN was related to the production of the type IV collagen by modified myoepithelial cells, whereas OPN was involved in the stromal formation of myxoid or hyaline tissues in pleomorphic adenomas. In summary, pleomorphic adenomas expressed the bone matrix proteins OSN and OPN.

Adenoma, Pleomorphic↗
PubMed2001

Abnormal venous structures in salivary gland tumors: vasculature characteristics of pleomorphic adenoma.

To clarify the diagnostic significance of abnormal venous structures present in salivary gland tumors, we examined 21 pleomorphic adenomas, 14 Warthin tumors, 1 oncocytic adenoma, 3 myoepitheliomas, 7 basal cell adenomas, 5 mucoepidermoid carcinomas, and 6 adenoid cystic carcinomas. Verhoeffvan Gieson staining was carried out and the morphology of the veins within the tumors was observed microscopically. Branching veins, thickened intima of the veins, discontinuous elastic membrane and multilayered elastic membrane were seen in 71.4%, 76.2%, 47.6% and 85.7% of pleomorphic adenomas, respectively, and were abundant and easily found in most cases. The abnormal venous structures were also found in other salivary gland tumors examined, but they were few in number and lacked variety. Elastic fibers extending radially into the surrounding stroma were seen in 66.7% of pleomorphic adenomas, and were not seen in other salivary gland tumors. Our results showed that a variety of abnormal venous structures are more abundant and more easily found in pleomorphic adenoma compared with other salivary gland tumors, and, in particular, that perivascular radiating elastic fibers are characteristic of pleomorphic adenoma. We emphasize that the presence of perivascular radiating elastic fibers may be helpful in diagnosing pleomorphic adenoma in small biopsy specimens.

Adenoma, Pleomorphic↗
PubMed2001

Recurrent pleomorphic adenoma of the palate in a child.

A rare case of recurrent pleomorphic adenoma of the palate in a 9-year-old boy is presented. Pleomorphic adenoma is relatively rare in children compared with its incidence in adults. However, it is the most common benign epithelial tumour of the salivary glands. The majority of pleomorphic adenomata in children occur in the major salivary glands, mainly the parotid gland. Pleomorphic adenomata of the minor salivary glands are rare in children and mainly occur in the palatal glands. Of the few cases of pleomorphic adenoma of the palate reported in children, only one case showed recurrence of the tumour after primary excision. We present the second case of recurrent pleomorphic adenoma of the palate in a child.

Adenoma, Pleomorphic↗
PubMed1998

Deletion of the p16 gene and microsatellite instability in carcinoma arising in pleomorphic adenoma of the parotid gland.

Carcinoma arising in pleomorphic adenoma of the salivary gland is a rare tumor, and its molecular aspects are unknown. Recent studies have revealed that malignant transformation of various human cancers may involve two different genetic alterations: inactivation of the p16 gene, which is a putative tumor suppressor gene, and genetic instability represented by microsatellite instability (MSI). However, so far, molecular investigations including p16 gene alteration and MSI have not been performed on carcinoma arising in pleomorphic adenoma. Both inactivation of the p16 gene and MSI were studied using DNA extracted from paraffin-embedded sections of carcinoma arising in pleomorphic adenoma. Samples also were analyzed for cyclin D1 gene amplification, which is thought to have oncogenic effects similar to those with inactivation of the p16 gene. One case showed the homozygous deletion of the p16 gene in the carcinoma, although hypermethylation of the p16 gene and amplification of the cyclin D1 gene were not observed in any cases. In two of four cases, MSI was observed. One case in two showed MSI in both the pleomorphic adenoma and the carcinoma. Results of this study suggest that two different genetic alterations, the inactivation of the p16 gene and genetic instability, play roles in the malignant transformation of carcinoma in pleomorphic adenoma. The MSI observed in the adenoma suggests that genetic alterations occur in pleomorphic adenoma.

Adenocarcinoma↗
PubMed1992

Polyploidy in pleomorphic adenomas with cytological atypia.

Occasionally, in fine-needle aspirates of pleomorphic salivary gland adenomas, considerable cytonuclear atypia is present, which may give rise to a false-positive diagnosis. In this study DNA cytophotometry was performed on Feulgen restained smears prepared from material obtained by needle aspirates of normal salivary glands (n = 4), pleomorphic adenomas with (n = 5) and without (n = 4) atypia and a carcinoma in a pleomorphic adenoma. The results showed a clear diploid DNA histogram in the specimens of normal salivary gland and pleomorphic adenomas without atypia. In contrast, in the pleomorphic adenomas with atypia a distinct polyploid pattern was present in three out of the five DNA histograms with DNA values in 2c, 4c and 8c ranges. In two of these cases a 16c peak was also present and in the two remaining cases tetraploidy was demonstrated. In the carcinoma a main stemline at 4c was found. This report once more emphasizes the possible atypia which may be present in FNA of pleomorphic adenomas of the salivary gland. The atypia is due to polyploidy in a histologically benign tumour.

Adenoma, Pleomorphic↗
PubMed1997

[Quantitative studies of oncogene ras P21 and P53 gene protein expression in the benign and malignant pleomorphic adenomas of salivary gland].

The oncogene ras P21 and P53 gene protein expression in the benign and malignant pleomorphic adenomas of salivary gland were quantitatively studied by flow cytometry and cellular immunofluorescence staining technique. The results showed that the ras P21 expression was found in 78% and 100% of the benign and malignant pleomorphic adenoma, respectively. The P53 protein was detected in 81% and 100% of the benign and malignant pleomorphic adenoma, respectively. The ras P21 and P53 protein were negative in the normal parotid tissue. The obvious different statistical significances of the fluorescence indexes (FI) in ras P21 and P53 expression were found between the benign and malignant pleomorphic adenoma (P < 0.001, respectively) as well as between the normal parotid tissue and the benign pleomorphic adenoma (P < 0.001, respectively). These results indicate that activation of ras oncogene and the mutation of P53 gene may play important roles in the tumourigenesis and the malignant transformation of the pleomorphic adenoma.

Adenoma, Pleomorphic↗
PubMed2003

[Recurrences of pleomorphic adenomas of the parotid: changing attitudes].

OBJECTIVE: The real issue of parotid surgery for pleomorphic adenoma is its risk of recurrence. The aim of this study was to compare the changing attitudes towards the pathology and surgical treatment in order to better define prevention and management of pleomorphic adenoma recurrences. MATERIAL AND METHOD: Histological study was performed after reviewing of slides originating from 100 patients with pleomorphic adenomas of the parotid gland, treated in our institution during the period May 1992 - November 2002. Study of the diagnostic value of fine needle cytology aspiration and MRI for pleomorphic adenoma diagnosis was performed for 181 patients operated on for parotid tumors. RESULTS: Hypocellular pleomorphic adenomas often have a thin capsule and constitute the most frequently encountered subtypes of recurrence. Pseudopodia are considered as an additional risk of recurrence. In our series, cytological study gave excellent diagnostic value with a sensitivity of 92% and a PPV of 96%. MRI study had a sensitivity of 83% and a PPV of 89%. CONCLUSIONS: According to these findings, enucleation surgery on a pleomorphic adenoma should not be performed any more. Parotidectomy techniques (total or superficial) constitute the surgical treatment of choice. The management of recurrences is based on surgery, with total parotidectomy and facial nerve preservation. The rôle of radiotherapy is still indeterminate.

Adenoma, Pleomorphic↗
PubMed1991

Muscle-specific protein expression in normal salivary glands and pleomorphic adenomas: an immunocytochemical study with biochemical confirmation.

Normal salivary gland myoepithelia are contractile cells with hybrid epithelial/myogenic ultrastructural features. It is known that these cells co-express the intermediate filaments cytokeratin, vimentin, and occasionally GFAP. This complex cytoskeletal immunophenotype is also reflected in multiple morphologic cell types of pleomorphic adenoma. At present, the myofilament complement of normal and neoplastic myoepithelium is not well defined. We have evaluated the expression of desmin and smooth and sarcomeric muscle actins in 11 normal salivary glands (six snap-frozen and five methacarn fixed) and 26 pleomorphic adenomas (11 snap-frozen and 15 methacarn fixed) by ABC-immunoperoxidase method. Two of 11 frozen pleomorphic adenomas contained the muscle-specific intermediate filament desmin, which is not found in the normal glands. This novel finding was confirmed by gel electrophoresis and immunoblot. Using specific antibodies, normal gland myoepithelial cells consistently contained muscle actin isoforms of the smooth muscle type but not sarcomeric muscle actins. Muscle actin expression by the neoplastic cells of pleomorphic adenoma was found in 13 of 26 tumors (six of 11 frozen tumors (desmin negative) and seven of 15 methacarn fixed tumors). In comparison to the normal myoepithelial cell, the transformed myoepithelial-like cells of pleomorphic adenoma are not always characterized by a muscle actin cytoskeleton. Expression of desmin intermediate filaments in pleomorphic adenomas appears to be a rare event that is independent of a muscle actin cytoskeleton.

Actins↗
PubMedDate not supplied

Parotid pleomorphic adenomas: delayed CT enhancement.

BACKGROUND AND PURPOSE: Weak or absent CT enhancement in pleomorphic adenomas of the parotid gland has been observed immediately after i.v. contrast administration. This feature can result in poor lesion conspicuity relative to both normal parotid tissue and other parotid abnormalities. The purpose of this study was to document the delayed CT enhancement characteristics of parotid pleomorphic adenomas and to preliminarily compare these results with the enhancement characteristics of other parotid gland tumors. METHODS: Preoperative CT scans from 18 pathologically proved parotid gland neoplasms were reviewed retrospectively. Lesions included eight pleomorphic adenomas, four Warthin's tumors, two squamous cell carcinomas, two mucoepidermoid cancers, one acinic cell carcinoma, and one melanoma metastasis. In all cases, axial CT was performed after the administration of 100 to 150 mL of i.v. contrast material, followed by delayed (average, 24 minutes; range, 13 to 34 minutes) coronal CT scanning. The mean normalized Hounsfield unit (HU) attenuation of each lesion was computed by drawing a region of interest around the entire mass and dividing the resulting HU value by that of the contralateral uninvolved parotid gland. RESULTS: For all eight pleomorphic adenomas, the degree of contrast enhancement increased and became progressively more uniform with time. Mean normalized axial lesion enhancement averaged 1.20 +/- 0.35 at 8 minutes, compared with 2.30 +/- 0.66 on the coronal scans at 24 minutes. For the 10 nonpleomorphic adenomas, no significant change was found in either the degree or pattern of contrast enhancement between the immediate and delayed CT scans. In these tumors, peak enhancement was reached early, during axial scanning. CONCLUSION: Delayed CT contrast enhancement is observed in parotid pleomorphic adenomas, increasing in both degree and homogeneity with time. This feature may be useful in selecting an appropriate contrast delay when scanning possible pleomorphic adenomas to improve lesion conspicuity and, potentially, to better distinguish these tumors from other parotid abnormalities.

Adenoma, Pleomorphic↗
PubMed1998

Cytogenetic analysis of 46 pleomorphic soft tissue sarcomas and correlation with morphologic and clinical features: a report of the CHAMP Study Group. Chromosomes and MorPhology.

With the aim of identifying objective cytogenetic-morphologic correlations, we evaluated 46 pleomorphic soft tissue sarcomas (mainly diagnosed originally as malignant fibrous histiocytomas) with clonal chromosome aberrations both cytogenetically and morphologically as part of an international collaborative study. By detailed histopathologic examination, most cases could be categorized into specific tumor types. Eight sarcomas were diagnosed as lipogenic (4 pleomorphic, 1 combined pleomorphic and myxoid/round cell, and 3 dedifferentiated liposarcomas), 19 as myogenic [11 leiomyosarcomas, 1 rhabdomyosarcoma, 4 myosarcomas not otherwise specified (NOS), and 3 probable myosarcomas NOS], 8 as myxofibrosarcomas, 1 as a malignant peripheral nerve sheath tumor, 1 as malignant mesenchymoma, 1 as extraskeletal osteosarcoma, I as sarcoma resembling proliferative fasciitis, and 7 as pleomorphic sarcomas NOS. In a three-grade system, 10 tumors were grade 2 and 36 were grade 3. The majority had highly complex karyotypes. A total of 24 recurrent abnormalities (defined by their presence in at least five cases) were detected: ring chromosomes, homogeneously staining regions (hsr) and/or double minute chromosomes (dmin), and structural rearrangement of 22 different chromosome bands or regions. The frequency and distribution of the recurrent karyotypic features were uneven. Grade 3 tumors displayed, on average, more aberrations per case than did grade 2 tumors. Nine of the selected abnormalities, including hsr/dmin and rearrangements of 19p13 and 19q13, were found only among the high-grade tumors. When the tumors were subdivided according to lineage of differentiation, the highest frequency of aberrations was seen in pleomorphic sarcomas NOS, followed by myxofibrosarcomas, myogenic sarcomas, and lipogenic sarcomas. None of the selected rearrangements was, however, specific for any of these subgroups. The sole consistent cytogenetic-morphologic association was that all three dedifferentiated liposarcomas had multiple abnormal clones, at least one of which contained supernumerary ring chromosomes. Due mainly to karyotype complexity, it therefore seems unlikely that cytogenetic analysis can assist in the differential diagnostic subclassification of pleomorphic sarcomas, nor was there any clear-cut indication that the karyotypic picture could be used to predict clinical outcome. Although the mean number of recurrent chromosome aberrations was almost twice as high in sarcomas that gave rise to metastases as among those that did not, no particular aberration was restricted to either of the two subgroups.

Adult↗
PubMed2000

Pleomorphic carcinoma of the breast: clinicopathological analysis of 26 cases of an unusual high-grade phenotype of ductal carcinoma.

AIMS: Pleomorphic carcinoma is a poorly described entity whose phenotype is not well recognized as within the morphological spectrum of breast carcinoma. The purpose of this report is to describe the clinicopathological features of this tumour, and to promote its recognition as an unusual high-grade morphological variant of mammary ductal carcinoma. METHODS AND RESULTS: Histological slides of breast carcinomas (N = 64) coded between 1978 and 1995 as having pleomorphic or anaplastic features were reviewed. Pleomorphic carcinoma (N = 26) was diagnosed when > or = 50% of the tumour manifested a pleomorphic cell population (> sixfold variation in nuclear size). Tumours of lobular origin were excluded. All neoplasms occurred in women with a mean age of 53 years. Patients underwent biopsy and/or mastectomy (n = 24) or lumpectomy (n = 2). The tumours' mean size was 54 mm. All were high-grade neoplasms. The pleomorphic cell population comprised 50-100% of the tumour; 31% had a prominent spindled morphology. Fifty-eight per cent of the tumours were initially misclassified by referring pathologists as sarcomas or carcinomas, possibly metastatic. Adjacent DCIS or a transition to classic ductal carcinoma was present in 73%. Five (19%) patients were stage I and three (12%) had stage IV disease. Axillary dissections yielded > or = 3 (mean 7.2) positive lymph nodes in 52%. Most (68%) tumours were aneuploid; a high S-phase (> 10%) was present in 63%. All neoplasms were ER negative and all but one were PR negative. p53 expression was present in 71%; none expressed bcl-2. c-erbB-2 was detected in four (19%) node-positive and in 0 (0%) node-negative cases (P = 0.01). Of 16 patients with follow-up, 6 (38%) were disease-free (mean, 74 months), four (25%) alive with disease (mean, 33 months) and six (38%) dead of disease at a mean of 22 months. CONCLUSIONS: Pleomorphic carcinoma is a prognostically unfavourable lesion and represents the extreme end of the morphological spectrum of grade III infiltrating ductal carcinoma.

Adult↗
PubMed2001

Pleomorphic rhabdomyosarcoma in children: four cases in the pediatric age group.

Pleomorphic rhabdomyosarcoma is considered rare and controversial, especially in children. Although pleomorphic rhabdomyosarcoma has been observed in children, its sparcity has taken it out of current childhood rhabdomyosarcoma classifications. We report four pediatric cases of pleomorphic rhabdomyosarcoma, review morphologic, immunohistochemical, and ultrastructural features, and discuss the rare need to include this category in children. The Soft Tissue Registry of the Armed Forces Institute of Pathology was searched for cases coded as "pleomorphic rhabdomyosarcoma" from 1970 to the present. Only cases in patients less than 21 years old were included. Clinical data, morphology, and immunohistochemical stains were reviewed and follow-up was obtained. Electron microscopy was performed on two cases. Molecular analysis by polymerase chain reaction was performed on one case with available material. Of four patients included, there were three boys and one girl. Patient ages ranged from 9 months to 10 years (median, 4.5 years). Tumors were located on the chest wall (n = 2) and one each on the upper and lower extremities. Tumor size ranged from 4.0 to 10.0 cm (median, 7 cm). Grossly, the tumors were lobulated and circumscribed. Microscopically, architectural patterns varied from solid to fascicular or storiform. All tumors had large, often multinucleated, polygonal, spindled or strap-like rhabdomyoblasts with abundant eosinophilic cytoplasm. Nuclear characteristics ranged from hyperchromatic to vesicular. Most tumor cells had large prominent nucleoli. Background rhabdomyoblasts varied from spindled to polygonal. No tumors displayed areas typical of embryonal or alveolar rhabdomyosarcoma. All tumors exhibited atypical mitotic figures. Immunohistochemistry revealed that the tumors were positive for the following markers: desmin (3/4), myoglobin (4/4), myoD1 (3/3), myf4 (3/3), and MSA (4/4). The two cases studied by electron microscopy both showed evidence for skeletal muscle differentiation. One case showed no evidence for a t(2;13) or t(1;13) translocation. Two patients were alive with no evidence of disease at 12 and 25 years. One patient was dead of disease at 9 years. Pleomorphic rhabdomyosarcoma is rare but exists in children. The diagnosis should be considered in pleomorphic sarcomas exhibiting skeletal muscle differentiation, which are otherwise devoid of typical areas or chromosomal changes of embryonal or alveolar rhabdomyosarcoma.

Antibodies, Monoclonal↗
PubMed2002

Pleomorphic sclerotic fibroma: a case report and literature review.

Pleomorphic sclerotic fibroma is a benign neoplasm exhibiting features of sclerotic fibroma and pleomorphic fibroma. We report another such case. The tumor presented as a firm, 0.5-cm, flesh-colored papule on the forehead of a 72-year-old white man for an unknown duration. Histologic examination revealed a neoplasm in which the superficial portion showed features of a pleomorphic fibroma, the deeper portion showed features of a sclerotic fibroma, and a transitional area was present in between. We propose that pleomorphic fibroma, sclerotic fibroma, and pleomorphic sclerotic fibroma form a spectrum. Pleomorphic sclerotic fibroma may be used as a broad diagnostic term to encompass the spectrum.

Aged↗
PubMed1993

Childhood rhabdomyosarcoma with anaplastic (pleomorphic) features. A report of the Intergroup Rhabdomyosarcoma Study.

The pleomorphic subtype of rhabdomyosarcoma (RMS) is now rarely diagnosed in both children and adults. Most cases previously called pleomorphic RMS are probably diagnosed as something else, most often embryonal RMS in children and malignant fibrous histiocytoma in adults. To analyze the concept of pleomorphic RMS in children, we reviewed the tumors of patients entered on the Inter-group Rhabdomyosarcoma Study (IRS I, II, and III). The presence of cells with lobated, hyperchromatic nuclei at least three times larger than the common tumor cell population (anaplastic cells) was selected as the main criterion. Of about 3,000 cases, 110 showed these types of cells, had sufficient histologic material, and had available follow-up data. These tumors were divided into two subgroups: Subgroup I tumors contained only scattered anaplastic cells, and tumors with foci or large sheets of anaplastic cells were classified as subgroup II. Besides the anaplastic-pleomorphic areas, most of these tumors had distinctive features of embryonal RMS (105 cases) and rarely had characteristics of alveolar RMS (five cases). The age distribution of these patients did not differ significantly from those whose tumors did not show the anaplastic features, the average being 6 years and the median 4 years. Lower extremity, retroperitoneum, and the head and neck region were the most common primary tumor sites. The 5-year survival rate was 60% for subgroup I tumors and 45% for subgroup II tumors compared with the survival rate of 68% for 482 IRS II embryonal RMS cases with no anaplastic-pleomorphic features. The lower survival rate for patients in subgroup II was statistically significant (p = 0.004) and similar to the unfavorable survival of patients with alveolar RMS and undifferentiated sarcoma. Because anaplastic cells are seen in many soft tissue sarcomas and in both embryonal and alveolar RMS in children, this feature is not sufficiently unusual to separate a pleomorphic subtype of RMS. The presence of anaplastic cells in aggregates or diffuse sheets throughout the tumor, however, portends a poor survival for these patients.

Antibodies↗
PubMed2001

Atypical pleomorphic astrocytoma in the pineal gland: case report.

OBJECTIVE AND IMPORTANCE: We report a rare case of pleomorphic astrocytoma in the pineal region that took a benign course despite pleomorphism. CLINICAL PRESENTATION: A 30-year-old woman suddenly developed right hemiparesis followed by loss of consciousness. A computed tomographic scan revealed a mass in the pineal region accompanied by obstructive hydrocephalus. Her symptoms improved after ventriculoperitoneal shunt surgery. INTERVENTION: The tumor was totally removed in an en bloc fashion using the occipital interhemispheric transtentorial route. Light microscopy revealed that the tumor had marked pleomorphism and multinucleated, bizarre giant cells, but neither mitosis nor necrosis was seen. Glial fibrillary acid protein was immunohistochemically positive in a few tumor cells. Retinal soluble antigen was negative. No reticulin network between the tumor cells was observed. A histological diagnosis of atypical pleomorphic astrocytoma was made. CONCLUSION: No signs of recurrence have been observed for 7 years after surgery without adjuvant therapy. Histologically, the tumor resembled pleomorphic xanthoastrocytoma or pleomorphic granular cell astrocytoma, but the immunohistochemical findings were not completely compatible with either diagnosis. This benign astrocytoma in the pineal gland with unique features is the first such case reported.

Adult↗