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Neurogenic tumors of the head and neck in children.

Soft tissue tumors make up 63% of all tumors in children. Tumors of the sympathetic chain make up 7.4% of tumors arising in children (nine new cases a year for every million children in USA) while neurofibrosarcomas make up 3.4% (2.4 new cases per year for every million children). There is a certain difference between the frequency of benign forms (rather elevated) and that of malignant forms (rather low). Diagnosis is possible by echo-scan, computed tomography, magnetic resonance imaging and fine-needle aspiration biopsy. As regards therapy, surgical resection represents the treatment of choice. In our experience, 35 neurogenic tumors in pediatric patients (8-16 years), arising in head and neck spaces, were observed and treated in the period 1976 and 1995. Twenty-six cases were schwannomas, six were neurofibromas and three were olfactory neuroblastomas. All the patients underwent surgery. Sacrifice of the affected nerve was necessary in 12 cases (all neurofibromas and eight neurinomas). In one case of olfactory aesthesioneuroblastoma a combined approach (extra-intracranial approach) was employed. Two patients are alive and disease-free with 5 and 7 years follow-up. As regards dysfunctional pathology following surgical resection, we report definitive facial nerve palsy in two cases, permanent laryngeal palsy in six cases, tongue dysfunction in one case and cheek hypoaesthesia in one case.

Adolescent↗

Correlation of type I insulin-like growth factor receptor (IGF-I-R) and insulin receptor-related receptor (IRR) messenger RNA levels in tumor cell lines from pediatric tumors of neuronal origin.

The insulin receptor-related receptor (IRR) is a member of the insulin receptor family. So far no ligand has yet been discovered for this receptor type (orphan receptor). IRR, insulin receptor (IR), and insulin-like growth factor-I receptor (IGF-I-R) are all tyrosine kinases. The cellular function of the IRR is not known. The expression of IRR mRNA is restricted to a few, e.g. neuronal tissues, and has also been found in neuroblastomas. Since tyrosine kinase receptors, including the IGF-I-R, may be involved in tumor genesis, we examined the expression of IRR mRNA and IGF-I-mRNA in 18 tumor cell lines using RT-PCR and the solution hybridization/RNAse protection assay. In particular, the mRNA levels of IRR and IGF-I-R were compared by semi-quantitative RT-PCR in seven neuroblastomas and 11 soft tissue sarcomas (STS), five of which were of neuronal origin. In all of the seven neuroblastoma cell lines and in five of the 11 STS cell lines, the IRR mRNA was detected. In addition, the IRR mRNA was expressed in rhabdomyosarcoma, in leiomyosarcoma, in one of the Ewing sarcoma and in the neurofibrosarcoma cell line. The last two tumor cell types are of neuronal origin. The levels of expression of IGF-I-R and IRR mRNA of the neuroblastoma cell lines were closely related (r = 0.82, P < 0.002). Furthermore, IRR mRNA was found only in cell lines that also expressed IGF-I-R mRNA. In conclusion, cell lines from pediatric tumors of neuronal origin express IRR mRNA simultaneously with a another tyrosine kinase receptor (IGF-I-R) mRNA. The tight coupling of their mRNA expression suggests a functional association of both receptors in the tumor cells.

Base Sequence↗

Fibrohistiocytic tumors of soft tissues. An immunohistochemical study of 183 cases.

183 cases of soft tissue tumors were studied utilizing the immunoperoxidase technique to demonstrate alpha-1-antitrypsin, ferritin and lysozyme. The series comprises 50 malignant lesions, 34 intermediate malignancy lesions, 99 benign lesions of fibrohistiocytic origin, and 23 malignant tumors of non fibrohistiocytic origin. The actual results of the study are as follows: alpha-1-antitrypsin, ferritin and lysozyme were always absent in 10 fibrosarcomas, 2 liposarcomas, 2 Ewing sarcomas, 3 synovial sarcomas, 4 neurofibrosarcomas, and 2 rhabdomyosarcomas, but in 24 malignant fibrous histiocytomas, 34 cases of dermatofibrosarcoma protuberans and 102 benign fibrohistiocytic lesions, these activities were present in a percentage that ranged between 12% and 38% (average 25%). Differences in the frequency of positive reactions did not occur between benign and malignant fibrohistiocytic lesions. The immunohistological examinations carried out have, therefore, only a very limited value for the practical diagnostic evaluation, but, when positive, are important to clarify the histogenesis of the tumor.

Ferritins↗

Nerve tumors of the hand and forearm.

Peripheral nerve tumors comprise less than 5% of all tumors of the hand. The most common solitary nerve tumor is the neurilemmoma, which arises from the neural sheath, is well encapsulated, minimally symptomatic, and may be surgically enucleated without producing a neurological deficit. Neurofibromas may be solitary, multiple, or associated with von Recklinghausen's disease. They are usually centrally placed with nerve fibers traversing the tumor mass making it more difficult to remove the tumor without producing permanent neurological damage. Malignant tumors include neurofibrosarcomas which often are very aggressive, requiring wide excision or amputation, and the rare neuroepitheliomas. Reported nerve tumors, intraneural in location but nonneural in origin, include fibrofatty infiltration of the median and digital nerves, intraneural lipoma, hemangioma, and ganglion cysts. These lesions may be treated by decompression or excision, depending on the nature of the tumor. Four unusual cases are described.

Adult↗

Principles of treatment for soft tissue sarcoma.

Soft tissue sarcomas (STS) are mesenchymal tumors arising from connective tissue elements and are grouped together based on a common biologic behavior. The most common histologic types include malignant peripheral nerve sheath tumors (schwannoma and neurofibrosarcoma) "hemangiopericytoma," fibrosarcoma, and malignant fibrous histiocytoma. These tumors are relatively slow growing yet locally invasive with a high rate of recurrence following conservative management. Appropriate preoperative planning and aggressive surgical resection often result in long-term remission or cure. Identification and evaluation of resection margins are paramount in appropriate case management. The addition of radiotherapy after surgical resection can aid in remission for incompletely resected masses. Systemic chemotherapy for STS should be considered for high-grade tumors with a moderate metastatic potential. Potential prognostic factors include grade, resection margins, size, location, histologic type, and previous treatment, with grade and margins being the most important. Tumor types classified as STS that differ slightly in their presentation or treatment, including synovial cell sarcoma, rhabdomyosarcoma, liposarcoma, and vaccine-associated STS in cats, are discussed. Soft tissue sarcomas can be a frustrating disease to treat, but adherence to solid surgical oncology principles can greatly increase the odds of good disease control.

Animals↗

[Multiple peripheral nerve tumors: update and review of the literature].

Multiple tumours of the peripheral nerves are seen only in neurofibromatosis. They are hereditary. They present and develop in a variety of different ways. Three main groups are distinguished: von Recklinghausen neurofibromatosis or type 1; bilateral acoustic neurofibromatosis or type 2 and schwannomatosis recently defined as type 3. The aim of this study was to clarify the clinical outcome of neurofibromatosis. The diagnosis is made purely on clinical grounds. Cranial MRI and slit lamp examination are useful for classification. Surgical management for peripheral nerve tumours is similar. Any new and rapid change noted at clinical examination (increase in volume, pain or neurological deficit) requires surgery because of potential malignant transformation of the neurofibroma into neurofibrosarcoma (type 1 only). The definitive treatment depends on the resectable character of the tumour which is usually only known after epineurotomy under operating microscope. In the event of resectable tumour (schwannoma) enucleation must be performed, preserving nerve continuity. In the event of unresectable tumour (neurofibroma), tumour resection is impossible without sacrificing nerve tissue. An epineurotomy must be performed. It prevents further deterioration. Interfascicular biopsy confirms the histological type. Our results are similar to those in other recorded studies. The unpredictable clinical course of neurofibromatosis makes prolonged follow-up mandatory.

Aftercare↗

Neurofibromatosis in monozygotic twins: a case report.

A case report is given of a pair of monozygotic twin girls with neurofibromatosis caused by a new mutation. The symptomatology was dominated by a neurofibrosarcoma on the leg of one twin and by a large plexiform neurofibroma on the neck of the other twin. Otherwise, the disease showed similar, although not identical or mirror-image distribution of subcutaneous neurofibromas and café-au-lait spots. The twins had identical HLA and blood group antigens and the same chromosome aberration. These case reports indicate that nonhereditary factors may influence the manifestations of neurofibromatosis. A review of the literature on monozygotic twins with neurofibromatosis is given.

Adult↗

Aberrant regulation of ras proteins in malignant tumour cells from type 1 neurofibromatosis patients.

Defects in the NF1 gene have been implicated in the inherited disorder neurofibromatosis type 1, which is characterized by several developmental abnormalities including an increased frequency of benign and malignant tumours of neural crest origin (neurofibromas and neurofibrosarcomas respectively). The NF1 gene encodes a ubiquitous protein homologous to p120GAP, the GTPase-activating protein (GAP) for the products of the ras protooncogenes. When expressed in non-mammalian systems, the region of the NF1 gene homologous to p120GAP produces a protein with GAP-like activity. Here we present evidence that the ras proteins in malignant tumour cell lines from patients with type 1 neurofibromatosis are in a constitutively activated state, as judged by the guanine nucleotide bound to them, and are necessary for cellular proliferation. These cells contain p21ras and p120GAP that are both functionally wild type, but barely any functional NF1 protein. Our results show that the NF1 protein is normally essential for correct negative regulation of ras proteins in the cell, even in the presence of normal p120GAP, and they support the hypothesis that NF1 is a tumour-suppressor gene whose product acts upstream of ras.

Antibodies, Monoclonal↗

CpG island methylation status and mutation analysis of the RB1 gene essential promoter region and protein-binding pocket domain in nervous system tumours.

A series of 136 nervous system tumours were studied to determine the methylation status of the CpG island contained within the promoter region of the RB1 gene, as well as mutation analysis of the essential promoter region and exons 20-24 (and surrounding intronic regions) coding for the protein-binding pocket domain. Methylation of the RB1 CpG island was detected in 26 samples corresponding to nine glioblastomas, three anaplastic astrocytomas, one mixed oligo-astrocytoma, one ependymoma, two medulloblastomas, two primary central nervous system lymphomas, two neurofibrosarcomas, and six brain metastasis from solid tumours. No inactivating mutations were found within the RB1 promoter region, whereas one glioblastoma and one oligodendroglioma displayed similar sequence variations consisting of 12 and 8 base pair deletions at intron 21. These results suggest that RB1 CpG island hypermethylation is a common epigenetic event that is associated with the development of malignant nervous system tumours.

CpG Islands↗

Microsatellite instability and promoter methylation as possible causes of NF1 gene inactivation in neurofibromas.

Neurofibromatosis type 1 (NF1) is a frequent hereditary disorder. One of the characteristic features of this disease is the development of neurofibromas. Since the NF1 gene is supposed to be a tumour suppressor gene, these neurofibromas should develop upon inactivation of both NF1 alleles. So far, mutation and deletion have been found to be involved in NF1 gene inactivation. However, these inactivating mechanisms explain the development of only a limited fraction of analysed neurofibromas. In this study, we investigated microsatellite instability (MSI) and promoter methylation as potential contributors to NF1 gene inactivation. As site-specific methylation in the NF1 promoter inhibits binding of transcription factors Sp1 and CREB, we studied the methylation status of their binding sites in particular. We analysed 20 neurofibromas and three neurofibrosarcomas, but did not find evidence for microsatellite instability or NF1 promoter methylation in any of the tumours. Thus, our data suggest that both microsatellite instability and promoter methylation are unlikely to be the major causes of NF1 gene inactivation in these tumours.

Base Sequence↗

Identification and functional characterization of thromboxane A2 receptors in Schwann cells.

Previous reports have demonstrated the presence of functional thromboxane A2 (TP) receptors in astrocytes and oligodendrocytes. In these experiments, the presence and function of TP receptors in primary rat Schwann cells (rSC) and a neurofibrosarcoma-derived human Schwann cell line (T265) was investigated. Immunocytochemical and immunoblot analyses using polyclonal anti-TP receptor antibodies demonstrate that both cell types express TP receptors. Treatment with the stable thromboxane A2 mimetic U46619 (10 microM) did not stimulate intracellular calcium mobilization in rSC, whereas T265 cells demonstrated a calcium response that was inhibited by prior treatment with TP receptor antagonists. U46619 also stimulated CREB phosphorylation on Ser133 in T265 cells and, to a lesser extent, in rSC. To identify potential mechanisms of CREB phosphorylation in rSC, we monitored intracellular cAMP levels following U46619 stimulation. Elevated levels of cAMP were detected in both rSC (20-fold) and T265 (15-fold) cells. These results demonstrate that TP receptor activation specifically stimulates CREB phosphorylation in T265 cells, possibly by a calcium- and/or cAMP-dependent mechanism. In contrast, TP receptor activation in rSC stimulates increases in cAMP and CREB phosphorylation but does not elicit changes in intracellular calcium.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

Unusual primary tumors of the heart.

Primary tumors of the heart, with the exception of atrial myxomas, occur rarely; tumors metastatic to or directly invasive of the heart are far more common. About 75% of primary tumors are benign, and 75% of these are atrial myxomas. The benign tumors include rhabdomyomas, fibromas, papillary fibroelastomas, hemangiomas, pericardial cysts, lipomas, hamartomas, teratomas, mesotheliomas, and paragangliomas or pheochromocytomas. The last 3 may also be malignant. The malignant tumors consist of various sarcomas: myxosarcoma, liposarcoma, angiosarcoma, fibrosarcoma, leiomyosarcoma, osteosarcoma, synovial sarcoma, rhabdomyosarcoma, undifferentiated sarcoma, reticulum cell sarcoma, neurofibrosarcoma, and malignant fibrous histiocytoma. Cardiac tumors produce a large variety of symptoms through any of 4 mechanisms. Their mass can obstruct intracardiac blood flow or interfere with valve function. Local invasion can lead to arrhythmias or pericardial effusions with tamponade. Bits of tumor can embolize, causing systemic deficits when the tumors are on the left side of the heart. Finally, the tumors may cause systemic or constitutional symptoms. Some tumors, of course, produce no symptoms and become evident as incidental findings. The most useful diagnostic tool is the echocardiogram, which in almost all cases precisely locates the tumor and defines its extent. The echocardiographic appearance may also allow quite accurate prediction of the tumor type and whether it is malignant or benign. Magnetic resonance imaging serves as the next most important test where the density of T1 and T2 images may allow tumor cell type identification. With few exceptions, these tumors require operative excision. Most benign tumors can be resected completely; a few, because of their large size, cannot be, and only tumor debulking may be possible. Heart transplantation should be considered for these patients. Many of the malignant tumors cannot be resected completely, either because of the extent of local spread and invasion or because of the frequent distant metastases. Transplantation may also be an option for those with extensive local disease. The long-term results for resected benign tumors are excellent; the long-term results for sarcomas are very poor, and there are few survivors. For patients with unresectable sarcomas, radiation and chemotherapy may be used, but without great expectation of successful results.

Fibroma↗

Mutation analysis of the p73 gene in nonastrocytic brain tumours.

Loss of heterozygosity (LOH) involving the distal chromosome 1 p36 region occurs frequently in nonastrocytic brain tumours, but the tumour suppressor gene targeted by this deletion is unknown. p73 is a novel gene that has high sequence homology and similar gene structure to the p53 gene; it has been mapped to 1 p36, and may thus represent a candidate for this tumour suppressor gene. To determine whether p73 is involved in nonastrocytic brain tumour development, we analysed 65 tumour samples including 26 oligodendrogliomas, 4 ependymomas, 5 medulloblastomas, 10 meningiomas, 2 meningeal haemangiopericytomas, 2 neurofibrosarcomas, 3 primary lymphomas, 8 schwannomas and 5 metastatic tumours to the brain, for p73 alterations. Characterization of allelic loss at 1 p36-p35 showed LOH in about 50% of cases, primarily involving oligodendroglial tumours (22 of 26 cases analysed; 85%) and meningiomas (4 of 10; 40%). PCR-SSCP and direct DNA sequencing of exons 2 to 14 of p73 revealed a missense mutation in one primary lymphoma: a G-to-A transition, with Glu291Lys change. 8 additional cases displayed no tumour-specific alterations, as 3 distinct polymorphic changes were identified: a double polymorphic change of exon 5 was found in one ependymoma and both samples derived from an oligodendroglioma, as follows: a G-to-A transition with no change in Pro 146, and a C-to-T variation with no change in Asn 204: a delG at exon 3/+12 position was identified in 4 samples corresponding to 2 oligodendrogliomas, 1 ependymoma and 1 meningioma, and a C-to-T change at exon 2/+10 position was present in a metastatic tumour. Although both LOH at 1 p36 and p73 sequence changes were evidenced in 4 cases, it is difficult to establish a causal role of the p73 variations and nonastrocytic brain tumours development.

Brain Neoplasms↗

[Pathology of soft tissue sarcomas: 238 cases of the childhood tumor registry].

Until April 1981 malignant soft tissue sarcomas were registered from 238 patients. Rhabdomyosarcoma was the most common tumor (115/238 = 48.3%). The embryonal subtype was predominantly seen among the rhabdomyosarcomas (83/115 = 72.2%). Rhabdomyosarcomas were localized most frequently in the head and neck area (40/115 = 34.8%), followed by genitourinary system (15/115), pelvis soft tissue (12), abdomen (10) and extremities (10). Non-rhabdomyosarcomatous soft tissue sarcomas (123/238 = 51.7%) were synovial sarcomas (20 = 8.4%), fibrosarcomas including spindle cell sarcoma (17 = 7.4%), leiomyosarcomas (12 = 5.0%), malignant tumors of the vascular system (11 = 4.6%) and neurofibrosarcomas (9 = 3.8%). Other types of sarcoma were extremely rare. 42 (17.6%) of all soft tissue sarcomas could not be classified histogenetically. Rhabdomyosarcomas could be diagnosed much more accurately (105/115 = 91.3%), compared to all other soft tissue sarcomas (99/121 = 81.8%). At present, the most difficult diagnostic problems remain with the tumors of connective tissue, in particular with fibrosarcomas and with the differential diagnosis of juvenile fibrosarcomas versus juvenile fibromatoses.

Adolescent↗

Giant neurofibromatosis of the chest wall: two patient reports.

Two patients with severely deforming giant neurofibromatosis of the chest wall secondary to von Recklinghausen's disease are presented. Pain, respiratory compromise, recurrent ulcerations, cosmetic considerations, and the malignant potential of these lesions indicated wide excision and reconstruction. It is impossible to completely eradicate all neurofibromas, which may affect virtually every nerve within the chest wall including the mediastinum. However, excision of the primary mass may reduce the possibility of malignant degeneration into neurofibrosarcoma or malignant schwannoma. This type of major, full-thickness chest wall resection is now possible using musculocutaneous flaps to achieve satisfactory closure with a single-stage procedure with minimal morbidity and a short hospital stay. At the 10-year follow-up, neither patient exhibited evidence of recurrence.

Adult↗

Sarcomatous transformation of neurofibromas. Comparative imaging with Ga-67, Tl-201, Tc-99m pentavalent DMSA and Tc-99m MIBI.

A 29-year-old man, with a history of von Recklinghausen's disease, presented with progressive dyspnea associated with a rapidly growing mass on the right chest wall. Plain radiograph and CT of the chest revealed a huge soft-tissue mass with central low-density area involving the right upper lung and chest wall. SPECT imaging with Ga-67 citrate, Tl-201 chloride, Tc-99m pentavalent DMSA (V-DMSA), and Tc-99m MIBI were performed to characterize the mass. The tumor concentrated Ga-67, Tl-201, and Tc-99m (V) DMSA, but not Tc-99m MIBI. Punch biopsy of the lesion revealed malignant transformation of a thoracic neuroma (neurofibrosarcoma). Subsequently, findings compatible with the presence of a multidrug resistance-1 (MDR1) gene in the tumor was documented, which may explain the poor uptake of Tc-99m MIBI. The patient did not respond to intensive chemotherapeutic regimens, and died 3 months later. This case demonstrates the potential use of combined radionuclide imaging for the detection of malignant transformation of neurofibroma, as well as for predicting tumor response to chemotherapy.

Adult↗

Reconstruction of late craniofacial deformities after irradiation of the head and face during childhood.

Little is known about the results of surgical management of late craniofacial abnormalities arising after irradiation of the head and face for treatment of childhood cancers. The clinical records of 10 children (4 males and 6 females) who received 4500 to 6500 rads (mean 5160 rads) of craniofacial radiation between birth and 8 years of age (mean 5 years) and who subsequently had reconstructive surgery were reviewed. Six of the 10 patients received orbital radiation, 3 received maxillary-midfacial radiation, and 1 patient underwent radiation to the frontal bone. Histologic tumor types included retinoblastoma (4), rhabdomyosarcoma (3), Ewing's sarcoma (2), and neurofibrosarcoma (1). In addition to radiation, 7 of the 10 patients underwent surgical resection or debulking of their tumors and 6 received adjuvant chemotherapy. All patients presented from 4 to 20 years after treatment (mean 10 years) with varying, but severe degrees of soft-tissue and bony hypoplasia of the irradiated territories. Onlay bone grafting with soft-tissue reconstruction by a combination of local pedicle flaps and dermal-fat grafts was initially performed in 9 patients, and an occipitoparietal bone-flap switch procedure was done in 1 patient. Late follow-up ranged from 11 months to 7.5 years (mean 34 months). A total of 8 secondary procedures were necessary in 4 of the 10 patients (40 percent). Of these 4 patients, major revisions were performed in 3 and minor adjustments in 1. In addition, 2 patients in whom secondary procedures had not been done would benefit from further reconstruction. Therapy for cancer of the head and face during childhood has profound and ongoing effects on the growth of soft tissue and bone.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Von Recklinghausen's disease (neurofibromatosis) associated with malignant pheochromocytoma.

An autopsy case of von Recklinghausen's disease (vRD) associated with malignant pheochromocytoma is reported. The patient is a 36-year-old Japanese male and diagnosed as vRD both clinically and pathologically. He died from right adrenal tumor with wide spread metastases to lungs and bone marrow. The tumors presented satisfactory histological features in favor of pheochromocytoma and neurosecretory granules were demonstrated in both primary and metastatic lesions ultrastructurally. Statistical study of 182, 673 autopsy cases from Annuals of Japanese Autopsy Cases was also done in order to investigate the relationship between vRD and associating tumors including benign and malignant pheochromocytoma. Cases with vRD showed significantly higher incidences of malignant Schwannoma, neurofibrosarcoma, intracranial glioma, and pheochromocytoma compared to that of non-vRD cases. Other malignancies revealed rather smaller incidences than non-vRD cases. These neurogenic tumors are to be principal life threatening problems in patients with vRD. Rare incidence of malignant pheochromocytoma in vRD is to become from low incidence of pheochromocytoma, though significantly greater than that of non-vRD cases.

Adrenal Gland Neoplasms↗