SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
A case of melanotic neuroectodermal tumor of infancy was presented. This tumor occurred in the right maxillary alveolar ridge of 3-month-old female infant, showing bluish enlargement of alveolar mucosa with the displacement of central deciduous incisor. We described the gross, microscopic, and ultrastructural findings of this tumor. This case appears to be the first case of MNTI, reported in a Korean.
Primitive neuroectodermal tumor (PNET) is a small round cell malignancy arising in soft tissue and bone, predominantly in older children and adolescents. We report the cytomorphologic features and findings of ancillary studies of eight fine needle aspiration (FNA) biopsies from three patients (7-year-old male, 12-year-old female, 9-year-old female). Two of the biopsies suggested the initial diagnosis of PNET of the chest wall, while the remaining six documented recurrent or metastatic disease. In one of these cases the primary diagnosis made by FNA biopsy enabled the pediatric oncologists to give specific therapy for the unresectable tumor and achieve remission. Local recurrences included the chest wall (two cases), pleura (one case) and pericardium (one case), while metastatic disease involved the supraclavicular lymph node and breast. All the cases consisted of small malignant cells with a high nuclear/cytoplasmic ratio and hyperchromatic nuclei without prominent nucleoli. Homer Wright rosettes were seen in only two of the aspirates, and neuropil and ganglion cells were not present. Ancillary studies, including electron microscopy (two cases), immunocytochemistry (four aspirates from two cases) and cytogenetics (11/22 translocation, one case) performed on the aspirated material were aids in making a specific diagnosis and excluded other small round cell tumors of childhood, such as malignant lymphoma, rhabdomyosarcoma and Ewing's sarcoma. The differential diagnosis between PNET and neuroblastoma can be difficult on the basis of an FNA biopsy alone, although light microscopic morphologic differences exist. Clinical features (e.g., age, primary site, metastatic patterns), catecholamine levels, electron microscopy and cytogenetics are necessary in establishing the correct diagnosis.
Three cases of melanomatic neuroectodermal tumor of infancy(MNTI) were studied.The tumor mainly consisted of small neuroblastic-like cells and pigmented large cuboidal cell,and infiltrated adjacent tissues.The main ultrastructural charactristics were the presence of some membranebound dense-core secretory granules,numerous free ribosomes and polysomes aggregaed in rosettes,occasional mitoses in the small cells;and four types of membranebound pigment granules corresponding to melanosomes at different stages of maturation in the pigment cell.immunohistochemical results indicated that both of main cells were positive reaction for NSE,negative for S-100.These facts suggested they are immature in and malignancy.Further,the isogenesis of the tumor cells and embryo optic cup cells were discussed.
Recurrence of a melanotic neuroectodermal tumor of infancy was clinically evident eight weeks after the original lesion had been surgically removed. Concentrations of urinary vanilmandelic acid were elevated immediately after surgery but returned to normal a month after removal of the tumor. The location of the recurrent tumor, the rapidity of recurrence, and the concentrations of urinary VMA favor a theory of neural crest origin.
A case of pigmented neuroectodermal tumor (melanotic progonoma) of the maxilla is presented. The treatment of this tumor is conservative surgical excision since the likelihood of recurrence is extremely slight. No case has ever been reported in which tumor metastasized.
Fusion of myeloma (P3X63-Ag 8.653) cells with spleen cells from BALB/c mice immunized with human neuroblastoma (SK-N-SH) cells yielded a hybridoma clone, referred to as 3XB7, with a unique pattern of reactivity to malignant neuroectodermal tumors except gliomas of low-grade malignancy. Indirect immunofluorescence staining under different conditions and Western blot analysis indicate that the 3XB7 MAb recognizes an intracellular cytoskeletal protein of M(r) 52K. Immunohistochemical studies with cryostat and paraffin-embedded sections from tumor biopsies revealed that the 3XB7 MAb specifically recognizes malignant neuroectodermal tumors and reacts negatively with other epithelial and mesenchymal tumors, e.g., carcinomas, lymphomas, and sarcomas as well as with normal adult and fetal brain tissues. Negative reaction was also observed with other small round cell tumors of childhood. Thus the 3XB7 antigen can be used for diagnosis of all stages of neuroblastomas, and its specific expression in gliomas with high-grade malignancy (grades III and IV) confer on it additional prognostic value.
BACKGROUND: Primitive neuroectodermal tumors (PNETs) are very rare. Malignant tumors of the cerebrum in young individuals are composed predominantly of undifferentiated cells, with moderate differentiation along either neuronal or glial lines. To our knowledge, cerebral PNETs in adults are extraordinarily rare and have been reported in only 11 cases, with little cytologic documentation in the literature. The cytopathologic, immunohistochemical and ultrastructural features of cerebral PNET arising in an adult male are presented. CASE: A cystic tumor, on computed tomography and magnetic resonance imaging, arose from the left frontal lobe in a 39-year-old man and contained histopathologic features of PNET. Specimens obtained from surgery revealed the presence of an undifferentiated type of PNET with moderate neuronal and glial differentiation and mild characteristic findings of peripheral PNET. The cytologic and histologic specimens showed evidence of a scattered pattern of blastic and undifferentiated tumor cells and a neural arrangement with Homer-Wright-like rosettes. Immunohistochemically, the tumor cells were glial fibrillary acidic protein, neuron-specific enolase, synaptophysin and CD-99 positive and epithelial membrane antigen, S-100 protein and vimentin negative. Ultrastructurally, neither microtubular structures nor intermediate filaments, except neurosecretory granules, were found in the tumor cells. CONCLUSION: Both immunohistochemical and ultrastructural studies on cytologic and histologic slides were important for the diagnosis of PNET because of establishing not only undifferentiated tumor cells but also neural and glial differentiation.
A neuroectodermal tumor of bone (NTB) is a small round cell tumor with Homer Wright rosettes. The differences in the nuclear profiles, proliferating activities, and biologic behavior between NTB and Ewing's sarcoma of bone (ESB) are still controversial. In this study, 11 cases of NTB and 12 cases of ESB were compared by a nuclear morphometrical approach using an image analyzer. In addition, the proliferative activity was also evaluated between the two groups by an immunohistochemical study using proliferating cell nuclear antigen (PCNA). The nuclei of NTB were found to be significantly more elliptical (Form Ell: NTB = 0.725, ESB = 0.743, P = 0.017) and irregular (Form Ar: NTB = 0.908, ESB = 0.933, P = 0.046) than those of ESB. The maximum diameter of the nuclei in NTB was larger than those of ESB (NTB = 6.92 micron, ESB = 6.33 micron, P = 0.017), however, there were no significant differences in the nuclear area between the two groups. Immunohistochemically, the mean PCNA score of the NTB (10 cases) were significantly higher than those of ESB (7 cases) (NTB = 25.9, ESB = 11.6, P = 0.005). The mitotic activities of NTB (17/10HPF) were also higher than ESB (6/10HPF) (P = 0.0008). There were no significant differences between the two groups in survival (log-rank test: P = 0.324) according to our small series. Our results suggest that these two tumors should be separated because their proliferating activity is different and they can be separated by some nuclear profiles.
A new human cell line, termed Muraoka, has been established from the recurrent tumor of a case of congenital primitive neuroectodermal tumor (PNET) arising at the temporofacial region of a male infant. The microscopic findings of this cell line were epithelioid, and the xenografted tumor in a nude mouse consisted of the malignant epithelioid cells. Immunohistochemically, the cells were positive for neuron-specific enolase, S-100 protein, carcinoembryonic antigen, cytokeratin, epithelial membrane antigen, and glial fibrillary acidic protein. These findings were quite similar to those of the epithelioid cells in the original tumor and of the xenografted tumor cells. Neither chromosomal abnormalities nor N-myc amplification were observed. Morphological differentiation after treatment with N6-2'-O-dibutyryladenosine 3':5'-cyclic monophosphate (Bt2-cAMP), all-trans-retinoic acid (RA), prostaglandin E1 (PGE1), and 5-bromo-2'-deoxyuridine (BrdU) showed two different results. Bt2-cAMP and PGE1 induced neuronal differentiation with the extension of neurites, whereas RA and BrdU predominantly induced Schwannian differentiation (flat cells). In these respects, the cell line Muraoka seems to be useful for studying characteristics of PNET as well as for developing the new treatments against such tumors.
Peripheral primitive neuroectodermal tumors (pPNETs) are aggressive, poorly differentiated neoplasms that occur in children and young adults. These tumors are associated with a peak incidence in the second decade and a slight male preponderance. Recently, Ewing sarcoma and pPNET tumors have been proven to carry identical translocations, the most common being t(11;22)(q24;q12). Intracranial Ewing sarcoma/pPNETs have rarely been described in the literature. We studied a case of intracranial pPNET arising in the right cavernous sinus of a 46-year-old man. On imaging, the tumor had both sellar and suprasellar components and was centered within the right parasellar region. Histologically, the tumor was composed of intermediate to large cells with round to oval hyperchromatic nuclei with distinct nucleoli. The cells contained a moderate amount of slightly basophilic cytoplasm. The tumor was markedly fibrotic and had collagen bands surrounding both individual and groups of cells. A large immunohistochemical panel was positive only for CD99 and vimentin. Fluorescence in situ hybridization did not show translocations associated with Ewing sarcoma/pPNET. However, a small percentage of these tumors can be negative for this translocation. In these cases, histology and immunohistochemical techniques in the absence of an alternative diagnosis are the only tools available to establish the diagnosis.
The occurrence of primitive neuroectodermal tumors located in the uterus is extremely rare. Eight cases have been described in the literature, and with the addition of this ninth case, we summarize treatment and outcome of PNET located in the uterine cavity.
We studied three cases of primitive neuroectodermal tumors surgically removed from the cauda equina region of adults. There was no clinical or radiological evidence of cerebellar medulloblastoma, other intracranial tumor or paraspinal sympathetic neuroblastoma. Two patients died: autopsies revealed no primary intracranial neoplasm. One patient is alive 3 years after surgery with no detectable intracranial tumor. The tumors had the light and electron microscopic features of primitive neuroectodermal tumors as described earlier in the literature. In addition, in all three cases many tumor cells could be stained for cytoplasmic neurofilament antigen.
BACKGROUND: Patients who survive retinoblastoma (RB) are at risk for having second nonocular tumors, usually osteosarcomas, which often are fatal. Such patients almost always have bilateral RB. METHODS: This article reports a woman who, at the age of 1 year had been cured of a unilateral RB by radiation therapy and enucleation. Eighteen years later, she had a sinonasal small cell tumor that rapidly recurred and proved fatal 2 months after surgical debulking. The tumor was studied by immunohistochemistry and electron microscopic (EM) examination. RESULTS: It showed diffuse neuron-specific enolase staining, focal weak staining for chromogranin, synaptophysin, and Leu-7 monoclonal antibodies in paraffin-embedded, B5-fixed tissue (Great Lakes Diagnostics, Troy, MI). EM study showed an undifferentiated primitive neuroectodermal tumor with many polyribosomes, simple cell junctions, few microtubules, and rare dense core granules. CONCLUSIONS: The combined immunohistochemical, ultrastructural, and clinical features of the tumor were interpreted as a sinonasal primitive neuroectodermal tumor with early neuronal differentiation. The tumor was pathologically indistinguishable from poorly differentiated olfactory neuroblastoma (ONB) and Ewing sarcoma.
The paper describes a large pigmented maxillary tumor in a 46-day-old infant. The histological examination showed the tumor to be a melanotic neuroectodermal tumor of infancy (MNTI). No raised urinary levels of vanilmandelic acid could be shown. The tumor was surgically removed and during a 5 1/2-year follow-up period there was no clinical evidence of recurrence. The origin, behavior and treatment of these rare tumors are discussed.
Chromosome 11p15 deletions occur frequently in several types of human cancer, both sporadic and familial, suggesting that a tumor suppressor gene is present within the deleted chromosome region. We carried out a restriction fragment length polymorphism analysis of chromosome 11p in two types of human brain tumors: malignant astrocytoma, the most common glial tumor in adults; and primitive neuroectodermal tumor (PNET), a malignant embryonic tumor that afflicts children. Loss of heterozygosity was found in 11/43 malignant astrocytomas (26%) and in 3/11 PNETs (27%). Deletion mapping revealed a region of loss on chromosome 11p (p15.4-pter) that was common to both tumor types. To determine whether the c-H-ras gene, located on chromosome 11p in the common region of deletion, was a candidate gene, we analyzed polymerase chain reaction products corresponding to all four c-H-ras coding exons for single-strand conformation polymorphisms. The absence of electrophoretic mobility shifts in tumor DNA compared to leukocyte DNA indicated that c-H-ras gene mutations were most likely not present. These results suggested that loss of a gene on chromosome 11p15 distinct from c-H-ras is an important step in tumorigenesis within the central nervous system in both children and adults.
Alterations in P16ink4 or in the gene encoding one of its ligands, cyclin-dependent kinase 4 (CDK4), have been reported in human glioma cell lines and primary tumors but not in primitive neuroectodermal tumors (PNETs), the most common malignant brain tumor of childhood. In this study the authors have examined DNA from 20 primary PNETs in children and from 20 malignant astrocytomas to assess the frequency of P16ink4 and CDK4 gene alterations associated with each type of tumor. Southern hybridization analysis revealed homozygous P16ink4 deletions in one (5%) of 20 PNETs and in seven (35%) of 20 malignant astrocytomas. The CDK4 gene amplification was evident in two additional astrocytomas, but not in any of the PNETs. In total, nine astrocytomas (45%) exhibited homozygous P16ink4 deletion or CDK4 gene amplification, but only one PNET (5%) demonstrated either gene alteration. These results indicate that the incidence of P16ink4 and CDK4 gene alterations in these two groups of tumors is different and suggest distinct pathogenetic etiologies may be associated with each neoplasm.
A series of 18 primitive neuroectodermal tumors (PNETs), the most common malignant central nervous system tumors of childhood, were analyzed with the recently developed approach of comparative genomic hybridization (CGH). In five cases, in which only small amounts of DNA were available, universal polymerase chain reaction was successfully applied to generate adequate probe material. In 15 tumors, chromosomal imbalances were elicited, most frequently involving chromosome 17 (loss of 17p and gain of 17q). Further recurrent imbalances included gains of the distal regions of 4p, 5p, 5q, 7q, 8q, and 9p. High-level amplifications were found on 2p24 (one case) and 8q24 (three cases), suggesting involvement of the protooncogenes MYCN and MYC, respectively. In one of these cases, Southern blot analysis could be performed, proving high-copy-number amplification of MYC. Interestingly, none of the three patients with high-copy-number amplifications of MYC responded to therapy.
We conducted a matched case-control study to investigate risk factors for the two most common types of brain tumors in children, astrocytic glioma and primitive neuroectodermal tumor (PNET). Since the study focused on gestational exposures, we restricted it to young children because these exposures would be expected to act early in life. Parents of 155 astrocytic glioma cases, 166 PNET cases, and controls identified by random digit dialing completed telephone interviews. Few associations occurred with the hypothesized risk factors, which were gestational exposure to alcohol, hair coloring products, farms, and substances containing N-nitroso compounds (passive smoking, makeup, incense, new cars, pacifiers, baby bottles, beer). Of the products studied that contain N-nitroso compounds, only beer was associated with a significantly increased risk of either tumor type [odds ratio (OR) for PNET = 4.0; 95% confidence interval (CI), 1.1-22.1; P = 0.04]. Elevated ORs for PNET were observed for farm residence of the mother during the pregnancy (OR = 3.7; 95% CI, 0.8-23.9; P = 0.06) and of the child for at least a year (OR = 5.0; 95% CI, 1.1-46.8; P = 0.04). Significant associations with astrocytoma were observed for mother's use of kerosene (OR = 8.9; 95% CI, 1.1-71.1; P = 0.04) and birth by Caesarean section (OR = 1.8; 95% CI, 1.1-3.2; P = 0.03). History of miscarriage was associated with a lower risk of PNET (OR = 0.5; 95% CI, 0.3-0.9; P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)