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PubMedDate not supplied

[Brachial plexus tumors--neurosurgical treatment].

Tumours of the brachial plexus according to present classification are included to soft tissue tumours. Because of rare occurrence of these tumours diagnostic and operative experience is relatively small. There is also a few number of publications regarding tumours of the brachial plexus. Therefore the aim of the study was to present our experience in the surgical treatment of tumours of the brachial plexus basing on the material of 5 cases treated in the years 1997-2001. There were 4 males and 1 female, age from 17 to 58 years old. Four patients were under 27 years old. In 3 cases tumours of the brachial plexus invaded the spinal canal through the intervertebral foramen and caused spinal cord compression (type A). In 2 cases tumours involved only plexus elements (type B). In 2 cases tumours were associated with neurofibromatosis type II. Five cases of neural sheath tumours included 2 schwannomas, 2 neurofibromas and 1 schwannoma malignum. All patients underwent surgery. In case of schwannomas and neurofibromas the surgical removal was radical without impairment of brachial plexus function. In case of a giant schwannoma malignum tumor, which caused flaccid paresis and symptoms of insufficient blood, supply with severe pain in the upper limb radical extirpation was also possible. In type A tumours in the first stage intraspinal part of the tumor was removed. Follow up observation lasted from 3 months to 4 years. The result of treatment of benign tumours was very good with complete function recovery of the upper limb, pain disappearance and no symptoms of recurrence in the long postoperative period. In case of malignant schwannoma in the early postoperative period both pain and symptoms of blood supply disturbances completely disappeared. The patient died 12 months after the operation because of tumor dissemination. Benign tumours of the brachial plexus can be effectively surgically treated using microsurgical techniques and, if necessary, nerve grafting. In case of malignant tumours many authors also recommend surgery with optimal sparing of the brachial plexus function and subsequent radio and chemotherapy. Low number A few cases in our series makes impossible to draw any epidemiological conclusions.

Adult↗
PubMed1992

[Endobronchial neurogenic tumors].

Endobronchial neurogenic tumours are exceptional and little known. The authors report two cases of such tumours: a neurofibroma of the right main bronchus in a 32 year old man and a schwannoma of the left main bronchus in a 10 year old child. Pneumonectomy was necessary in both cases due to destruction of the pulmonary parenchyma distal to the obstruction. The incidence of this type of tumour is estimated to be between 0.2 and 4%. They may be either schwannomas or neurofibromas, the discovery of which always raises the problem of the possible association of von Recklinghausen's disease malignant forms, neurogenic sarcomas or malignant schwannomas may also be encountered. The diagnosis is based on endoscopy which reveals the tumour and allows biopsy. Treatment of these essentially benign tumours should be conservative, provided the diagnosis is made early, prior to parenchymal destruction. The prognosis is poor in the malignant forms and chemotherapy may be useful in malignant schwannomas.

Adult↗
PubMedDate not supplied

Characterization of nuclear size, ploidy, DNA histogram type and proliferation index in 79 nerve sheath tumors.

The distribution values of ploidy, of the DNA histogram type, of the proliferation index and of the nuclear area are described in a series of 79 nerve sheath tumors including 7 traumatic neuromas, 55 primary and 9 recurrent benign schwannomas, 5 benign neurofibromas and 3 malignant tumors. The nuclear parameters were computed on Feulgen-stained nuclei (from archival formalin-fixed paraffin-embedded materials) by means of digital cell image analysis. The results show that 20-30% of benign nerve sheath tumors exhibit an abnormal nuclear DNA content (DNA index > 1.30). Such a feature was observed in the four groups of benign tumors, i.e. primary and recurrent schwannomas, neurofibromas and even traumatic neuromas. Aneuploid tumors exhibited triploid, hypertriploid or polymorphic DNA histogram types. The three malignant tumors under study were aneuploid. Lastly, the nuclear area and proliferation index measurements did not allow any clear distinction to be made between the four groups of benign tumors on the one hand, and between the benign and malignant tumors on the other.

Adult↗
PubMed1992

Nerve sheath tumors: evaluation with CT and MR imaging.

Tumors of nerves are classified into benign (schwannoma and neurofibroma) and malignant nerve sheath tumors. Schwannomas almost always occur as solitary lesions, whereas neurofibromas may occur alone or in a greater number, especially in patients with the peripheral form of von Recklinghausen's disease. Benign nerve sheath tumors often present as asymptomatic, slowly growing soft tissue masses. Although malignant nerve sheath tumors are relatively rare, a sudden increase in the size of a lesion, in particular in a patient with neurofibromatosis, should raise the suspicion of malignant change. On computed tomography (CT) and magnetic resonance imaging (MR) a benign nerve sheath tumor usually appears as a well-defined, oval, spherical or fusiform mass with smooth borders and distinct outlines, located in the subcutaneous tissue or centered at the expected anatomic location of a nerve, with displacement of adjacent soft tissues. Generally nerve sheath tumors have a low density on unenhanced CT scans. On MR they are isointense to muscle on T1-weighted images, whereas on T2-weighted images the signal intensity is high. Both on CT and MR the degree of contrast enhancement is moderate to marked and may be homogeneous or inhomogeneous. MR has become the method of choice for evaluating the anatomic location, contour, and relation of a nerve sheath tumor to adjacent neural, vascular, and muscular structures. The imaging criteria for malignant nerve sheath tumors are not specific enough to distinguish them from other malignant soft tissue tumors, so that neither CT nor MR can establish a definite diagnosis.

Adolescent↗
PubMed2002

Hepatic trisegmentectomy for 29 patients with huge liver neoplasms.

OBJECTIVE: To evaluate retrospectively the feasibility and effect of hepatic trisegmentectomy in therapy of huge neoplasms of the liver. METHODS: From July 1993 to October 1999, 29 patients with huge hepatic neoplasms underwent hepatic trisegmentectomy. Of these, 23 patients suffered from primary liver cancer, 1 hepatic infiltration of gallbladder cancer, 1 metastasis of colon cancer, 1 hepatic angiosarcoma, 1 hepatic neurofibroma, and 2 huge liver cysts. Twenty-six patients were subjected to right trisegmentectomy and the rest 3 left trisegmentectomy. All trisegmentectomies were performed under normothermic interruption of the porta hepatis at single time and these interruptions lasted 15 to 40 minutes. RESULTS: The relatively good effect was seen in our series. The 1-, 3-, 5-year survival rates for primary liver cancer patients were 63.6%, 36.4% and 27.3%, respectively. The survival period for the patients with hepatic infiltration of gallbladder cancer and liver metastasis of colon cancer was 6 months. Those with hepatic angiosarcoma, hepatic neurofibroma and huge liver cysts have been surviving 35, 26, 25 and 40 months, respectively. Major complications were noted in 5 patients, and one (3.4%, 1/29) died. CONCLUSION: Hepatic trisegmentectomy is safe and effective in treatment of huge hepatic neoplasms if its indications and operative techniques are properly mastered.

Adolescent↗
PubMed2004

Mechanisms of injury in operative brachial plexus lesions.

OBJECT: The authors focus on injury mechanisms involved in 1019 operative brachial plexus injuries (BPIs) managed between 1968 and 1998 at Louisiana State University Health Sciences Center (LSUHSC). METHODS: Data regarding these mechanisms of injury were obtained via retrospective chart reviews of patients who had undergone operations at LSUHSC. Five main mechanisms of injury to the brachial plexus occurred in the series. These included 509 stretch/contusion injuries (49%) with four patterns of presentation in 366 patients: 208 C5-T1 nerve injuries; 75 C5-7, 55 C5-6 injuries; and 28 involving the C8-T1 or C7-T1 nerves. Stretch/contusion injury was followed in frequency by gunshot wound (GSW), resulting in 118 injuries (12%). Most of the 293 involved plexus elements had some gross continuity when surgically exposed. Seventy-one lacerations involved the brachial plexus (7%), including 83 sharp lacerations caused by knives or glass; 61 blunt transections due to automobile metal, fan, and motor blades, chain saws, or animal bites. Nontraumatic BPIs included 160 cases of thoracic outlet syndrome or 16% of the total of 1019 BPIs. There were 161 tumors (16%) of neural sheath origin including 55 solitary neurofibromas (34%), 32 neurofibromas associated with von Recklinghausen disease (20%), 54 schwannomas (34%), and 20 malignant nerve sheath tumors (20%) removed. Obstetrical BPI was not included in the original series; however, the current literature is reviewed in this paper. CONCLUSIONS: The conclusion of this study is that the brachial plexus can be injured by multiple mechanisms of which stretch/contusion injury is the most frequently encountered, followed by GSWs.

Anastomosis, Surgical↗
PubMed1991

Immunohistochemistry as a diagnostic aid in the interpretation of unusual mesenchymal tumors of the uterus.

Sixty-three pure mesenchymal tumors of the uterus were studied to explore the value of immunostaining in the diagnosis of unusual mesenchymal tumors encountered in the uterus, some not reported previously. Each tumor was evaluated using a panel of immunostains including actin, desmin, vimentin, S-100 protein, and cytokeratin. The final classification, which incorporated the immunohistochemical findings, resulted in the identification of 33 relatively common pure mesenchymal tumors (13 benign and malignant endometrial stromal tumors and 20 benign and malignant smooth muscle tumors) and 30 uncommon tumors (five leiomyosarcomas with osteoclastic giant cells, two xanthomatous leiomyosarcomas, one melanotic schwannoma, one pure rhabdomyosarcoma, one neurofibroma, five plexiform tumorlets, and 15 combined smooth muscle-stromal tumors). The normal endometrial stroma, present in 14 cases, invariably showed a negative reaction for all antibodies. With rare exceptions, the pure endometrial stromal tumors displayed a negative immunoreaction for all antibodies utilized, while the pure smooth muscle tumors consistently showed a positive reaction for actin. Only the two tumors of neural origin (a neurofibroma and a melanotic schwannoma) reacted with S-100 protein. Immunostaining influenced most the final classification of neoplasms initially interpreted as uterine tumors with a sex-cord stromal pattern, endometrial stromal tumors that diverged from the classic lesions by having a spindle cell component, and intravascular leiomyomas with areas of compact proliferation of small round cells with prominent vascularity. All tumors in these three groups were reclassified as combined smooth muscle-stromal tumors following immunohistochemical studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗
PubMed1975

[Difficulties with diagnosis of intrathoracic neurogenic tumors (author's transl)].

58 patients have been operated for neurogenic tumors of the mediastinum. Diagnostic problems are discussed. Some rare cases are presented: a neurofibroma of the n. vagus with mediastinal localization, a cavernous hemangioma, a leiomyoma and a fibrosarcoma; all of these imitating typical neurogenic tumors. The patient with the fibrosarcoma had several operations for recurrence of the histologically benign neurofibroma and died 4 years later of generalized fibrosarcoma. Because of this possible histological error all seemingly benign neurogenic tumors should be removed early.

Adolescent↗
PubMed1990

Neoplasms of the peripheral nervous system.

Neoplasms of the peripheral nervous system arise from the cellular sheath surrounding the nerve trunks, that is, the pluripotential Schwann cells and related cells, and rarely affect the feet. When present, they are most frequently associated with the autosomal dominantly inherited neurofibromatosis 1. This condition has been related to chromosome 17, and it appears, from in vitro experiments, to involve defects in tyrosine metabolism. Hence, the most common neoplasm is the neurofibroma. Distinct criteria have been established for a diagnosis of neurofibromatosis 1, so that a single pedal neurofibroma may not represent this complex. However, if the complex is present, it is necessary to consider the possibility of malignant transformation to a neurofibrosarcoma. Although malignant peripheral nerve neoplasms are extremely rare in the feet, they may arise in the context of neurofibromatosis 1, or independently. Other benign or malignant schwannomas may (rarely) also arise in the feet. Surgical excision of benign lesions, according to established standards for tumor surgery, is usually curative, but a detailed personal and familial history, along with adjunctive radiologic procedures and biopsy, is necessary to determine the nature of the lesion. Since (endocrine and) other abnormalities may complicate neurofibromatosis 1, surgical procedures must not be undertaken until the patient has been medically cleared and is carefully monitored. A high mortality rate is associated with malignant peripheral neurogenic tumors, especially those arising in the context of neurofibromatosis 1. It should be recalled that neurologic manifestations in the foot may represent non-neoplastic conditions as well as peripheral nerve tumors (or other tumors involving those nerves) that are proximal to the foot and ankle area.

Adult↗
PubMed1988

Immunohistochemical evaluation of Leu-7, myelin basic-protein, S100-protein, glial-fibrillary acidic-protein, and LN3 immunoreactivity in nerve sheath tumors and sarcomas.

The collective expression of five antigens produced in immature or mature myelin-producing glia was evaluated in nerve sheath tumors and spindle cell sarcomas with histologic features of schwannomas. Myelin-associated glycoprotein (Leu-7), myelin basic-protein (MBP), S100-protein, and, in most cases, glial-fibrillary acidic-protein (GFAP) and HLA-DR/Ia (LN3) immunoreactivity were evaluated immunohistochemically using commercially available antibodies on 53 benign nerve sheath tumors and 12 sarcomas. Leu-7 immunoreactivity was detected by a monoclonal antibody in 12 of 16 schwannomas, 12 of 20 neurofibromas, and 17 of 17 traumatic neuromas. No Leu-7 positivity was seen in the sarcomas. Distinct heavy MBP immunoreactivity, assessed using polyclonal antibodies, was identified only in all 17 traumatic neuromas. Extensive S100-protein positivity was seen in 15 of 16 schwannomas, 17 of 20 neurofibromas, and 17 of 17 traumatic neuromas. Extensive LN3 immunoreactivity was seen in Schwann cells of 50% of the nerve sheath tumors analyzed; however, it was also present in associated interdigitating reticulum cells; GFAP immunoreactivity was not detected. These data suggest that Leu-7 is an important marker of Schwann cell neoplasms, although it is not superior to S100 protein. Moreover, combined immunohistochemical evaluation of potential Schwann cell markers including Leu-7, MBP, GFAP, and LN3 using commercially available antibodies offers no advantage over analysis of S100-protein immunoreactivity alone.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Transplacental induction of peripheral nervous tumor in the Syrian golden hamster by N-nitroso-N-ethylurea. A new animal model for von Recklinghausen's neurofibromatosis.

Multiple peripheral nervous tumors were induced in 45 of 60 (75.0%) Syrian golden hamsters by transplacental administration of N-ethyl-N-nitro-sourea. Moreover, melanomas, pheochromocytomas, and Wilms' tumors developed in six (10.0%), three (5.0%), and 13 (21.7%) animals, respectively. The histologic, immunohistochemical, and electron microscopic findings of the peripheral nervous tumors were similar to those of human neurofibroma, and their growth pattern and distribution resembled those of human von Recklinghausen's neurofibromatosis (VRNF). The occurrence of melanoma, pheochromocytoma, and proliferative foci of melanin-containing cells in neurofibroma suggests that the targets of ENU in hamsters are the neural crest-derived cells. With its high incidence of Wilms' tumor, the hamster with ENU-induced tumors is considered to be a good animal model for human neurocristopathy, including VRNF.

Animals↗
PubMed1989

[Dumbbell neurogenic tumors. 5 cases (4 thoracic, 1 lumbar)].

Benign in more than 90% cases, dumbbell neurogenic tumors are rare. It was 3 thoracic schwannome and 1 thoracic ganglioneuroma and 1 lumbar schwannoma are reported. In 2 cases complete removal was performed by thoracotomy, in another case thoracic removal was incomplete with leateag of spinal fluid, laminectomy was necessary 3 months later and in a third case laminectomy was performed first because of paraplagia and thoracotomy one month later. In lumbar case a two ways procedure in 3 weetes space permitted complete removal, a monoparesia and sphincters troubles, regressive spontaneously in 5 months, complicated first performed laminectomy. Schwannome and benign neurofibroma are the most frequent tumors. Latero vertebral situation in chest radio or in abdominal ultrasonography must induce neurogenic tumors diagnosis. Myelography or tomodensitometry confirms intraspinal extension when osseous signs are present on vertebral radiographies. In thoracic localization a one stage combined resection gives the lowest morbidity. In lumbo-sacral localization tumoral large size requires a combined approach, which can be performed in a single stage. Recklinghausen's association in neurofibroma (4 to 16%) exposes to malign evolution risk (12 to 13%).

Adult↗
PubMed1987

Immunoreactivity for Leu-7 in neurofibrosarcoma and other spindle cell sarcomas of soft tissue.

Monoclonal antibodies to Leu-7 have been reported to recognize a constituent of myelin-associated glycoprotein. Because of this, the authors studied 20 cases of neurofibrosarcoma (NFS), 7 of leiomyosarcoma (LMS), 3 of fibrosarcoma (FS), 8 of malignant fibrous histiocytoma (MFH), 5 of monophasic spindle cell synovial sarcoma (MSS), 5 of neurilemmoma, and 5 of neurofibroma for Leu-7 reactivity, to determine its utility in differential diagnosis. Selected examples of each tumor type were also studied ultrastructurally. Leu-7 was compared with the expression of S-100 protein, myelin basic protein, desmin, cytokeratin, and epithelial membrane antigen in the 43 neoplasms. Fifteen examples of NFS, 2 of LMS, and 2 of MSS were Leu-7+; 2 neurofibromas and 4 neurilemmomas also demonstrated reactivity with this antibody. In contrast, all cases of FS and MFH were Leu-7-. Synovial sarcomas could be effectively separated from NFS by reactivities for cytokeratin and epithelial membrane antigen in the former, but not the latter, lesions. However, LMSs and NFSs demonstrated significant immunocytochemical overlap, including shared positivity for S-100, desmin, and myelin basic protein in several cases. These results suggest that Leu-7 has restricted utility in immunohistochemical diagnosis, and must be utilized only in concert with other antigens. Moreover, it would appear that in selected instances, smooth-muscle and neurogenic sarcomas must be separated on the basis of clinical, histopathologic, and ultrastructural features alone.

Adolescent↗
PubMed1987

Perineurial cells in culture. An immunocytochemical and electron microscopic study.

Perineurium is a cellular ensheathment protecting the nerve fascicles, i.e., groups of Schwann cell-axon units, in the peripheral nerves. To date, culturing of perineurial (PN) cells has not been reported. Pieces of nerve fascicles from sciatic nerves of adult Wistar rats were used as a source of PN cell cultures. Outgrowth of very large squamous cells was observed from about 90% of the explants. The cells divided slowly and their very large, flattened phenotype and their sheetlike growth patterns were distinct from those of the other connective tissue cells of peripheral nerves, such as Schwann cells or endoneurial fibroblasts. Selected pieces were re-explanted 1 to 10 times and about 1 to 5% of all explants gave rise to cultures which were apparently free from other cell types. They were concluded to be originated from the perineurium according to their light microscopic and ultrastructural properties and their ability to express specific antigens; the cells produced laminin and formed patches of basement membrane material on their surface. These characteristics are not associated with fibroblastic cells and the lack of S-100 protein differentiated the PN cells from the Schwann cells. Furthermore, cultured PN cells expressed fibronectin which is not produced by Schwann cells. PN cells showed characteristically prominent cytoplasmic actin containing stress fibers and staining with antibodies to vimentin showed arrays of intermediate filaments. The cells were negative for cytokeratin, glial fibrillary acidic protein, desmin, and factor VIII-related antigen indicating that they were not related to epithelial, glial, muscle-derived, or endothelial cells, respectively. PN cell cultures maintained their viability up to 5 to 8 passages and did not become overgrown by other cell types. Samples from normal human sciatic nerve and from neurofibromas from patients with von Recklinghausen's neurofibromatosis were cultured as described for rat sciatic nerve. The resulting cultures contained cells which had characteristics resembling those of cultured rat PN cells when studied at the light microscopic level. The present novel method to grow PN cells in cultures provides a possibility to study the specific functions of these cells under conditions not influenced by stimuli from e.g., the axons or the Schwann cells. The present data also provides evidence that PN cells, in addition to Schwann cells and fibroblasts, take part in the formation of neurofibromas.

Animals↗
PubMed1987

Peripheral nerve sheath tumors of the head and neck.

The head and neck region is a common location for benign peripheral nerve sheath tumors (PNST) and a rare site for malignant PNST. The diagnostic distinction between schwannoma (neurilemmoma) and benign neurofibroma remains clinically and prognostically important. Most benign PNST are schwannomas, and these do not have a recognized malignant potential. Malignant PNST arise de novo or from benign neurofibromas. The definitive diagnosis of malignant PNST may be difficult or impossible using only routine light microscopy. Electron microscopy and immunohistochemistry are special techniques that may be helpful. The prognosis in patients with malignant PNST depends heavily on the extent of surgical excision, size of the primary tumor, and presence or absence of von Recklinghausen's neurofibromatosis.

Fibrosarcoma↗
PubMed1985

Malignant peripheral nerve sheath tumors of the orbit: a clinicopathologic study of eight cases.

Eight adult patients with malignant peripheral nerve sheath tumors of the orbit are described. Only two of the patients were known to have von Recklinghausen's neurofibromatosis. The typical clinical history included the development of a mass in the superonasal quadrant of the orbit, which was palpable immediately beneath the skin of the lid. There was a definite tendency for the lesions to arise in, or grow along, the supraorbital nerve--including posteriorly through the superior orbital fissure to the Gasserian ganglion, and even as far posteriorly along the trigeminal rootlets to the pons. Delays in pathologic diagnosis, which beclouded the true nature of the process, led to multiple recurrences, eventuating in five known fatalities out of the eight patients. In addition to intracranial extension, pulmonary metastases and regional cervical metastases were encountered. Once recognized for their diagnostic value, the histopathologic patterns are highly distinctive: biphasic populations of spindled and epithelioid cells; sheets of epithelioid cells or clusters demarcated by delicate reticulin fibers or thicker collagenous trabeculae; malignant plexiform patterns; and neurotubular patterns. Pure spindle cell populations were encountered only in the two patients with von Recklinghausen's disease, and in each, either a pre-existent benign neurofibroma or a coexistent plexiform neurofibroma was found in the pathology specimens. The best management of this condition depends upon early clinical and pathological recognition, leading to radical surgery, which usually consists of orbital exenteration combined with intracranial extirpation of as much of the trigeminal nerve as possible. Postoperative radiotherapy and chemotherapy after radical surgery might also be advisable.

Adult↗
PubMed1985

Case report of malignant primary nerve sheath tumor arising in the female pelvis.

This paper reports a malignant primary nerve sheath tumor (MPNST) which originated in the obturator nerve in a 54-year-old woman. That the tumor originated in the nerve sheath is supported by the site of occurrence, which was consistent with the obturator nerve, an arrangement of cells similar to that in schwannoma, and that extracellular basement membrane was noted ultrastructurally. This tumor was classified not as malignant schwannoma but as a nerve sheath fibrosarcoma because the matrix of tumor tissues contained abundant mucinous materials, some tumor cells were fibroblastic, and the clinical change was rapid. In general, with plexiform neurofibroma there is a familial manifestation and it occurs as a complication of von Recklinghausen's disease, associations not demonstrated in this patient. From these findings, this tumor is considered to be an extremely rare nerve sheath fibrosarcoma which originated from a malignant change in a sporadic and solitary plexiform neurofibroma.

Collagen↗
PubMed1979

[Comments on the problem of differential diagnosis of tumours of the nerve sheaths in angiography (author's transl)].

The article describes the special features governing the assessment of angiographic findings in tumours of the nerve sheaths. Considerations of differential diagnosis, especially between neurinoma and neurofibroma, are discussed. Likewise, the problems of differential diagnosis of such tumours against neoplasms of the tissue of the soft parts, are also discussed. Angiography permits only a limited determination of the degree of malignancy of the neurinoma and neurofibroma. It is always mandatory to correlate these findings with the histological findings. However, angiography does seem to be justified as an additional examination technique, since it supplies fundamental pointers for surgery.

Adolescent↗