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Proton-decoupled 31P MRS in untreated pediatric brain tumors.

Proton-decoupled (31)P and (1)H MRS was used to quantify markers of membrane synthesis and breakdown in eight pediatric patients with untreated brain tumors and in six controls. Quantitation of these compounds in vivo in humans may provide important indicators for tumor growth and malignancy, tumor classification, and provide prognostic information. The ratios of phosphoethanolamine to glycerophosphoethanolamine (PE/GPE) and phosphocholine to glycerophosphocholine (PC/GPC) were significantly higher in primitive neuroectodermal tumors (PNET) (16.30 +/- 5.73 and 2.97 +/- 0.93) when compared with controls (3.42 +/- 1.62, P < 0.0001 and 0.45 +/- 0.13, P < 0.0001) and with other tumors (3.93 +/- 3.42, P < 0.001 and 0.65 +/- 0.30, P < 0.0001). Mean PC/PE was elevated in tumors relative to controls (0.48 +/- 0.11 versus 0.24 +/- 0.05, P < 0.001), but there was no difference between PNET and other tumors. Total choline concentration determined with quantitative (1)H MRS was significantly elevated (4.78 +/- 3.33 versus 1.73 +/- 0.56 mmol/kg, P < 0.05), whereas creatine was reduced in tumors (4.89 +/- 1.83 versus 8.28 +/- 1.50 mmol/kg, P < 0.05). A quantitative comparison of total phosphorylated cholines (PC+GPC)/ATP measured with (31)P MRS and total choline measured with (1)H MRS showed that in tumors a large fraction of the choline signal (>54 +/- 36%) was not accounted for by PC and GPC. The fraction of unaccounted choline was particularly large in PNET (>78 +/- 7%). The pH of tumor tissue was higher than the pH of normal brain tissue (7.06 +/- 0.03 versus. 6.98 +/- 0.03, P < 0.001).

Brain↗

Primitive pineal tumor with retinoblastomatous and retinal/ciliary epithelial differentiation: an immunohistochemical study.

A one year old boy was found to have a large tumor encompassing the pineal region and extending towards the third and lateral ventricles and quadrigeminal plate. The tumor was composed mostly of small, undifferentiated cells. Some small cells were arranged in Flexner-Wintersteiner rosettes and a few displayed fleurettes. The tumor contained immature cartilage and skeletal muscle and numerous clusters of pigmented epithelial-like cells which, histologically, resembled those found in melanotic neuroectodermal tumors of infancy (retinal anlage tumors) and retinal or ciliary epithelium. Immunologic stains demonstrated neurofilaments synaptophysin and retinal S-antigen in some of the small cells and transthyretin in some of the epithelial-like cells. The findings indicate that certain primary pineal parenchymal tumors have features in common with tumors of the ocular medullary epithelium.

Brain Neoplasms↗

Monoclonal antibody to stage-specific fetal brain 68-kDa glycoprotein (FGP68) revealed increased FGP68 expression in human primary brain tumors.

We have produced a novel rat IgG(2a) monoclonal antibody against a stage-specific fetal brain glycoprotein of 68 kDa (FGP68), and succeeded in applying it to staining paraffin sections. To gain some insight into the pathobiological significance of this FGP68, this monoclonal antibody was used in immunohistochemical studies to compare the expression of FGP68 and Ki-67 antigen (MIB-1) in 235 primary brain tumors. Approximately half of the glioblastomas multiforme (GBMs) (44/75) and anaplastic astrocytomas (9/17) as well as some astrocytomas (5/30), medulloblastomas (2/14) and primitive neuroectodermal tumors (2/10) had tumor cells that expressed FGP68; however, pilocytic astrocytomas (0/7), oligodendrogliomas (0/15), ependymomas (0/6), schwannomas (0/21), meningiomas (0/22) and pituitary adenomas (0/18) did not express FGP68. The values of the MIB-1 labeling index were statistically higher in GBMs (0.005< P<0.01, Wilcoxon rank-sum test) and anaplastic astrocytomas (0.025< P<0.05) that expressed FGP68 than in those that did not. Normal brain tissue from 20 individuals aged 3-75 years was negative for FGP68 and MIB-1. We conclude that primary brain tumors express FGP68, one of the oncofetal proteins derived from fetal brain, and that FGP68 expression in certain brain tumor cells may depend, in part, on proliferation potential. Based on the possibility that the stage-specific FGP68 plays an important role in brain embryogenesis, some of FGP68-expressing tumor cells might phylogenetically revert to more primitive cells.

Animals↗

Meningeal melanocytoma: a case report and literature review.

The clinicopathologic, immunocytochemical, and electron microscopic features of a case of meningeal melanocytoma arising in the phylum terminale are reported. Meningeal melanocytoma is an uncommon tumor that must be distinguished from metastatic or primary malignant melanoma, meningeal melanocytic nevi, pigmented meningioma, pigmented schwannoma or neurofibroma, and pigmented primitive neuroectodermal tumor. This is a difficult differential diagnosis that can be best archived by complementing histological examination with a selected panel of antibodies and, most important, electron microscopic study. The distinctive ultrastructural appearance of most of these lesions point to this technique as the gold standard in pigmented proliferations of the nervous system.

Aged↗

Cell kinetics of glial tumors.

The development of monoclonal antibodies against bromodeoxyuridine (BUdR) has made it possible to study the cell kinetics of individual brain tumors more extensively and more rapidly than previously possible. Over the past several years, we have performed in situ labeling studies of 502 neuroectodermal tumors with BUdR. The results have shown that the BUdR labeling index (LI), or percentage of cells in DNA synthesis, is generally higher in malignant gliomas; that histologically similar tumors may have different proliferative potentials, demonstrated by differences in the BUdR LIs; and that a higher LI indicates a higher proliferative potential as well as a shorter time to recurrence and duration of survival. Double-labeling studies with BUdR and iododeoxyuridine, performed to analyze the cell cycle progression in 29 gliomas, revealed that S-phase duration (Ts) was fairly uniform (mean +/- SD: 8.9 +/- 2.0 hours) regardless of the differences in the LIs. Nevertheless, the potential doubling time (the time for a tumor cell population to double in the absence of cell loss) varied from 2 days to over a month, being very short for tumors with a high LI, and correlated with the BUdR LIs (Tp = 17.8/LI0.77; r = 0.95). The cell cycle time calculated for gliomas with LIs of 1-20% was 1-2 days. These parameters are useful in determining the dose, duration, and interval of chemotherapy and in evaluating the effectiveness of treatment. Thus, cell kinetics studies not only elucidate the growth characteristics of individual gliomas but may also benefit to patients by providing a more precise prognosis and may be considered in the selection of treatment modalities.

Antibodies, Monoclonal↗

Fine-needle aspiration (FNA) cytology diagnosis of small round cell tumors: value and limitations.

Small round cell tumors (SRCTs) are a group of malignancies (non-Hodgkin lymphoma, neuroblastoma, retinoblastoma, hepatoblastoma, nephroblastoma, rhabdomyosarcoma, small cell anaplastic carcinoma, Ewing sarcomal peripheral neuroectodermal tumor, and desmoplastic small round cell tumor), characterized both cytologically and histologically by a predominantly small round to oval, and relatively undifferentiated cells. Together they form a formidable group and an overwhelming majority of childhood malignancies. The patients may present in later (inoperable) stage with huge intrathoracic and intraabdominal mass, when chemotherapy and/or radiation therapy may be the first or only line of treatment. As a less invasive procedure fine needle aspiration (FNA) cytology has definite advantage over surgical excision biopsy to arrive at a tissue diagnosis before initiation of therapy. Because of the morphologic similarities, the SRCTs may pose a differential diagnostic problem in the practice of clinical cytology, especially when they are poorly differentiated. Important cytomorphological features, which help in the identification of various SRCTs include completely dissociated cell population and lymphoglandular bodies (cytoplasmic fragments) in non-Hodgkin lymphoma (NHL), eosinophilicfibrillar material and Homer-Wright rosettes along with cellular processes in neuroblastoma, acinar formation in hepatoblastoma, blastema cells with tubular differentiation in nephroblastoma, tadpole shaped cells in embryonal rhabdomyosarcoma, extreme nuclear molding and perinuclear blue inclusion in small cell anaplastic carcinoma (SCAC), irregular, punched out and large cytoplasmic vacuolations due to glycogen in Ewing sarcoma, and sheets of undifferentiated small round cells surrounded by collageneous stroma in desmoplastic small round cell tumor (DSRCT). Some of these features such as nuclear molding, rosette, and acinar formation are noticed in more than one type of SRCTs. Moreover, the characteristic cytomorphological features may be present in 70-80% cases and for categorization of the remaining cases, contribution from ancillary studies is essential. It is suggested that cytomorphological features along with one or more of the parameters such as special stains (cytochemistry), immunocytochemistry (ICC), electron microscopy (EM), tissue culture, DNA ploidy, karyotype and molecular analysis can increase the diagnostic accuracy of SRCTs. However, these facilities may not be available in all the laboratories, especially in the developing countries, and even if available in a limited form, a tissue diagnosis has to be offered often by FNA cytology based on morphological features, as a life saving measure in seriously ill patients before the results of ancillary studies are finalized.

Biopsy, Fine-Needle↗

The role of fine-needle aspiration biopsy in the initial diagnosis of pediatric bone and soft tissue tumors: an institutional experience.

The use of fine-needle aspiration biopsy (FNAB) in the initial evaluation of pediatric bone and soft tissue tumors is controversial, especially for those patients being considered for histiogenetic-specific therapeutic protocols, e.g., the Intergroup Rhabdomyosarcoma Study Group, the Pediatric Oncology Group. We retrospectively reviewed 33 consecutive FNAB specimens (28 primary tumors, 5 metastases) from 32 pediatric patients (< or = 19 yr of age), none of whom had a previously established tumor diagnosis. In one patient, FNAB of the primary tumor and a presumed axillary metastasis were obtained concomitantly. The cytomorphologic analysis included osteosarcoma, eight patients; rhabdomyosarcoma, five; neuroblastoma, five; Ewing's sarcoma/primitive neuroectodermal tumor, four; Langerhans' cell histiocytosis, three; and one each synovial sarcoma, undifferentiated sarcoma, infantile myofibromatosis, fibroma, chondroblastoma, chondromyxoid fibroma, and desmoplastic small round-cell tumor. Ancillary studies, e.g., immunocytochemical analysis, were used in 13 cases. Cytogenetic analysis helped to confirm one Ewing's sarcoma [t (11;22) (q24;q12)] and one synovial sarcoma [t(X;18) (p11;q11)]. With adequate FNAB specimens, a histogenetic-specific diagnosis was rendered in 27 (93%) of 29 cases, and all were correctly recognized as either benign or malignant. One case each of Langerhans' cell histiocytosis, chondroblastoma, and infantile myofibromatosis yielded unsatisfactory specimens. Fibroma and desmoplastic small round-cell tumor were initially misclassified as nodular fasciitis and rhabdomyosarcoma, respectively. Of 18 patients clinically eligible for histogenetic-specific therapy protocols, an accurate diagnosis was obtained in 17 patients. With a multidisciplinary approach and judicious use of ancillary studies, FNAB represents a highly accurate and cost-effective technique for the diagnosis of pediatric bone and soft tissue tumors, especially sarcomas, and should be considered as a viable diagnostic technique for pediatric therapeutic protocols.

Adolescent↗

[Epidemiology and pathology of brain tumors in childhood].

The nervous system is the most common site for the development of solid neoplasms in children. The most frequent oncotype is the pilocytic astrocytoma, followed by the medulloblastoma. Primitive undifferentiated neuroectodermal tumors occur primarily in childhood; problems of pathogenesis of these neoplasms are discussed, as well as their relationship with central nervous system development.

Adolescent↗

Dianhydrogalactitol and neural tumors: an in vitro, in vivo preclinical evaluation.

The effects of dianhydrogalactitol on human neuroblastomas in vitro and in vivo as heterotransplants in nude mice were determined. Four neuroblastoma lines and three primitive neuroectodermal tumor lines were found, in vitro, to have different sensitivities to the drug. The most sensitive in in vitro assays was the neuroblastoma line SK-N-Mc. Tumors from patients resistant to cyclophosphamide were sensitive to dianhydrogalactitol in vitro and in nude mice. The lack of increased cytotoxicity in vitro with concentrations greater than 12 micrograms/ml and the lowered degree of weight loss in mice treated with 6 mg/kg/day x 5 consecutive days compared to 15 mg/kg/day x 2 days (either in sequence or with a 3-day interval) suggest that clinical trials with 5-day courses or constant infusions may be more effective than intermittent pulsed doses.

Animals↗

Identification of endosialin, a cell surface glycoprotein of vascular endothelial cells in human cancer.

Cell surface antigens of transformed cells are the traditional targets for antibody-guided detection and therapy of solid neoplasms. Alternative targets may be found in the tumor stroma, which contains newly formed blood vessels, reactive fibroblasts, and extracellular matrix proteins. The F19 cell surface glycoprotein of reactive fibroblasts is a prototypic stromal antigen since it is found in the stroma of > 90% of common epithelial cancers but is absent or expressed at low levels in normal tissues and benign epithelial tumors. In the present study, we define an additional tumor stromal antigen, FB5, that is selectively expressed in vascular endothelial cells of malignant tumors. Immunohistochemical analysis of 128 tumors identified FB5 in endothelial cells in 67% of the samples (including 41 of 61 sarcomas, 26 of 37 carcinomas, and 18 of 25 neuroectodermal tumors) whereas normal blood vessels and other adult tissues tested lacked FB5 expression. In vitro studies showed that FB5 is a M(r) 165,000 cell surface glycoprotein, comprised of a M(r) 95,000 core polypeptide and highly sialyated O-linked oligosaccharides but few if any N-linked sugars, and that the FB5 gene is located on chromosome 11q13-qter. The restricted tissue distribution of the FB5 protein, which we refer to as endosialin, suggests strategies for tumor imaging and therapy that are aimed primarily at the tumor vasculature.

Adult↗

"Undifferentiated" small round cell tumors of the sinonasal tract: differential diagnosis update.

Sinonasal tract neoplasms composed of light microscopically seemingly "undifferentiated" small round cells often generate considerable diagnostic difficulty. Although the careful review of H&E-stained sections remains of critical and central importance in this evaluation, the recent improvements in the immunohistochemical diagnostic armamentarium and molecular diagnostic techniques applicable to paraffin-embedded tissue samples may add diagnostically valuable information. Accordingly, this review will discuss the differential diagnosis of undifferentiated small blue cell tumors of the sinonasal tract based on the light microscopic and clinical features and, as needed, the results of these ancillary studies. Tumors discussed include olfactory neuroblastoma, sinonasal undifferentiated carcinoma, small cell undifferentiated (neuroendocrine) carcinoma, undifferentiated (lymphoepithelioma-like) carcinoma, malignant melanoma, pituitary adenoma, Ewing sarcoma/peripheral neuroectodermal tumor, rhabdomyosarcoma, mesenchymal chondrosarcoma, small cell osteosarcoma, synovial sarcoma, extranodal natural killer/T-cell lymphoma, nasal type, and extramedullary plasmacytoma.

Carcinoma, Small Cell↗

Aberrant expression of tumor suppressor proteins in the Ewing family of tumors.

BACKGROUND: Deregulation of tumor suppressor gene function and abrogation of cell cycle control are common features of malignant neoplasms, but corresponding data on Ewing sarcomas and primitive neuroectodermal tumors are relatively scarce. We studied the expression of 4 tumor suppressor proteins in the Ewing family of tumors (EFTs). DESIGN: We examined a series of 20 pediatric EFTs for abnormal expression of p16(INK4a), p14(ARF), p21(WAF1), and pRB by immunohistochemical analysis of pretreatment, nondecalcified archival specimens. Clinical follow up was available in all cases (median, 21 months; range, 5-103 months). Five patients presented with metastatic disease, 8 had no evidence of disease at last follow up, and 12 had an adverse outcome (death or progressive tumor posttherapy). RESULTS: Twelve cases (60%) demonstrated abnormal expression of at least one tumor suppressor protein. There were 11 cases (55%) with loss of p21(WAF1) expression, 4 (20%) with down-regulation of p16(INK4a), 2 (10%) with absence of pRB, and one case (5%) with loss of p14(ARF) expression. Loss of p16(INK4a) expression correlated with metastatic disease at presentation (P =.026), and showed a trend toward shortened survival (P =.20). The p21(WAF1), p14(ARF), and pRB status was not significantly correlated with either metastatic disease at presentation or outcome. CONCLUSION: Abrogation of the G1 checkpoint was common in this series of EFTs, and down-regulation of p21(WAF1) and p16(INK4a) were the most frequent findings. Loss of p16(INK4a) expression may identify a subset of cases with a more aggressive phenotype.

Adolescent↗

[The effects of high-dose ifosfamide in the treatment of bone and soft tissue sarcomas].

From January 1990 to December 1995 we treated 35 patients (pts) with bone and soft tissue sarcoma with ifosfamide (IFM). Sixteen patients had measurable metastatic pulmonary lesion and 9 had primary lesion. Histology of the tumor included osteosarcoma in 13 pts, Ewing sarcoma in 5 pts, malignant fibrous histiocytoma of bone in 2 pts, synovial sarcoma in 7pts, primitive neuroectodermal tumor in 2 pts, and other in 7 pts. The IFM at the dose of 12-18g/m2 (mean 15. 4g/m2) for 5 to 8 days continuous infusion was administered to patients in each treatment course. The uroprotector, mesna, was also given concomitantly in 60-100% dose of IFM. Eighteen pts received one course of IFM treatment. Other pts received 2 to 8 courses of IFM treatment at three to four week intervals. The overall response rate was 40% (PR in 14 pts, NC in 18 pts, and PD in 3 pts). The response rate of 13 pts with osteosarcoma was 54% (PR in 7 pts) and 30% in 15 pts with soft tissue sarcoma (PR in 5 pts).

Adolescent↗

Categorization of pediatric neoplasms by immunostaining with antiprekeratin and antivimentin antisera.

Forty-six tumors in children were examined using light microscopy and subsequently frozen sections were stained with antiprekeratin and antivimentin antisera, so that the tumors could be classified by tissue of origin. Except for two adrenal cortical carcinomas and four liver tumors, most epithelial neoplasms continued to produce prekeratin filaments, a characteristic of normal epithelial cells. Tumors and cells of epithelial origin did not produce vimentin filaments, whereas normal and neoplastic mesenchymal cells did. Tumors with both epithelial and mesenchymal components produced vimentin filaments in mesenchymal areas and prekeratin in epithelial areas. Tumors of lymphoid origin showed variable production of vimentin filaments, depending on the amount of cell cytoplasm, but did not contain prekeratin filaments. Of the neuroectodermal tumors, only the ganglioneuroma contained vimentin filaments and none contained prekeratin filaments. Thus, antibodies to both prekeratin and vimentin filaments are useful in diagnosing childhood neoplasms and studying their histogenesis.

Child↗

New drug developments for patients with metastatic soft tissue sarcoma.

For the subgroup of patients with inoperable gastrointestinal stromal tumors, progress has been made by the rapid development and approval of the targeted therapy imatinib mesylate. Small round cell sarcomas (SRCT), such as Ewing/primitive neuroectodermal tumor, desmoplastic SRCT, and rhabdomyosarcoma, are chemotherapy-sensitive and potentially curable malignancies that are treated with multimodality dose-intensive neoadjuvant protocols regardless of size or overt metastatic disease. However, the number of effective cytotoxic agents for the treatment of patients with metastatic so-called adult soft tissue sarcoma is limited, especially when patients have failed anthracycline- and ifosfamide-based chemotherapy.

Antineoplastic Agents↗

Morphologic characterization of spontaneous nervous system tumors in mice and rats.

Spontaneous rodent nervous system tumors, in comparison to those of man, are less well differentiated. Among the central nervous system (CNS) tumors, the "embryonic" forms (medulloblastoma, pineoblastoma) occur both in rodents and humans, whereas the human "adult" forms (gliomas, ependymomas, meningiomas) have fewer counterparts in rodents. In general, the incidence of spontaneous CNS tumors is higher in rats (>1%) than in mice (>0.001%). A characteristic rat CNS tumor is the granular cell tumor. Usually it is associated with the meninges, and most meningeal tumors in rats seem to be totally or at least partly composed of granular cells, which have eosinophilic granular cytoplasm, are periodic acid-Schiff reaction (PAS)-positive, and contain lysosomes. Such tumors are frequently found on the cerebellar surface or at the brain basis. Rat astrocytomas are diffuse, frequently multifocal, and they invade perivascular spaces and meninges. The neoplastic cells with round to oval nuclei and indistinct cytoplasm grow around preexisting neurons, producing satellitosis. In large tumors, there are necrotic areas surrounded by palisading cells. Extensive damage of brain tissue is associated with the presence of scavenger cells that react positively with histiocytic/macrophage markers. The neoplastic astrocytes do not stain positively for glial fibrillary acidic protein; they probably represent an immature phenotype. In contrast to neoplastic oligodendroglia, they bind the lectin RCA-1. Astrocytomas are frequently located in the brain stem, especially the basal ganglia. Rat oligodendroglial tumors are well circumscribed and frequently grow in the walls of brain ventricles. Their cells have water-clear cytoplasm and round, dark-staining nuclei. Atypical vascular endothelial proliferation occurs, especially at the tumor periphery. Occasionally in the oligodendrogliomas, primitive glial elements with large nuclei occur in the form of cell groups that form rows and circles. Primitive neuroectodermal tumors of rats, such as pineal tumors or medulloblastomas, appear to have features similar to those found in man. In mice, the meningeal tumors are mostly devoid of granular cells and the astrocytomas are similar to those occurring in rats, whereas spontaneous oligodendrogliomas are observed extremely rarely. Tumorlike lesions, such as lipomatous hamartomas or epidermoid cysts, are occasionally encountered in the mouse CNS. It is suggested that we classify rodent CNS lesions as "low grade" and "high grade" rather than as "benign" and "malignant." The size of CNS tumors is generally related to their malignancy. Tumors of the peripheral nervous system are schwannomas and neurofibromas or neurofibrosarcomas consisting of Schwann cells, fibroblasts, and perineural cells. Well-differentiated schwannomas are characterized by S-100 positivity and the presence of basement membrane. They show either Antoni A pattern with fusiform palisading cells or Antoni B pattern, which is sparsely cellular and has a clear matrix. The rat develops specific forms of schwannomas in the areas of the submandibular salivary gland, the external ear, the orbit, and the endocardium. Spontaneous ganglioneuromas occur in the rat adrenal medulla or thyroid gland. Compared to experimentally induced neoplasms, the spontaneous tumors of the rodent nervous system are poor and impractical models of human disease, although they may serve as general indicators of the carcinogenic potential of tested chemicals.

Animals↗

Medulloblastomas in late middle age and the elderly: report of 2 cases.

Medulloblastomas may be difficult to recognize in late middle age and the elderly because of their rarity and their histological similarity, particularly in frozen sections, to common, poorly differentiated, metastatic tumors, notably the small cell carcinoma of lung. This report describes the occurrence of medulloblastomas in a 66-year-old male (case 1) and a 65-year-old female (case 2). Both tumors appeared radiologically as cystic cerebellar masses of irregular shape and variable intensity on magnetic resonance imaging; in each case microscopic examination revealed a primitive neuroectodermal tumor with focal astrocytic differentiation and desmoplasia. Case 1 died 23 months after surgery; an autopsy revealed extensive dissemination of the tumor to the bone marrow, small collections of malignant cells in the spinal subarachnoid space, and no evidence of local recurrence. Case 2 is well 29 months after her operation. The possibility of a medulloblastoma should be considered when a solitary cerebellar lesion is discovered in a middle-aged or elderly patient without a demonstrable extraneural primary site.

Aged↗

Congenital supratentorial and infratentorial peripheral neurogenic tumor: a clinical, ultrastructural, and immunohistochemical study.

Congenital neoplasms of the central nervous system are extremely rare, although they have been well documented since the earliest reports from the mid-19th century. Medulloblastoma, other primitive neuroectodermal tumors, and various types of gliomas have comprised the majority of cases. This report describes a highly unusual infratentorial and supratentorial tumor presenting as a scalp mass in a neonate who experienced in utero distress. The supratentorial mass extended through a defect in the skull to the parietooccipital lobe, and the infratentorial aspect involved the 9th and 10th cranial nerves in the region of the cerebellopontine angle. A complex spindle cell neoplasm incorporating peripheral nerve sheath and vascular characteristics was further characterized by electron microscopy and immunohistochemistry. Based upon these studies, the tumor was interpreted as a congenital schwannoma with divergent vascular differentiation. The child has been tumor-free for approximately 2 years after the initial operative procedure.

Brain Neoplasms↗