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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Von Recklinghausen's neurofibromatosis is an autosomal dominant disease involving peripheral nerves and central nervous system. Obstructive hydrocephalus in this disease represents a common finding when it is due to the development of infratentorial neoplasm. Nevertheless, the occurrence of isolated nonneoplastic aqueductal stenosis in patients affected by neurofibromatosis has been described rarely. The authors report two cases of primary nontumoral aqueductal stenosis associated with Von Recklinghausen's disease who were diagnosed by CT scan and MRI. The pathogenesis of aqueductal narrowing in neurofibromatosis is discussed.
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PMID:[Neurofibromatosis and stenosis of the aqueduct of Sylvius. A magnetic resonance assessment]. 212 63

A 75-year-old man presented with a right cerebellopontine angle tumor 11 months after complete macroscopic resection of a right acoustic neurilemoma. Histological examination of the recurrent tumor showed a malignant spindle-cell neoplasm with positive staining for S-100 protein. The patient had no stigmata of von Recklinghausen's disease. It is proposed that this recurrence represents progression from a benign to a malignant acoustic nerve-sheath tumor, an event that is extremely rare outside the clinicopathological context of neurofibromatosis.
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PMID:Recurrence of acoustic neurilemoma as a malignant spindle-cell neoplasm. Case report. 223 Sep 79

During a routine physical examination in 1976, a 54-year-old man was noted to suffer from hearing difficulty and continuing tinnitus of his right ear. He had, however, no further consultations for the next five years, although the symptom persisted and gradually worsened. In May 1981, he experienced complete hearing loss in his right ear. A computed tomography disclosed no abnormalities, and other laboratory tests were unremarkable. In September 1981, the patient began to complain of paresthesia of the right angle of the mouth and tongue, right-sided facial paralysis, and walking difficulty. A repeated computed tomography showed a tumor at the right cerebellopontine angle region. A clinical diagnosis of acoustic schwannoma was made. The first operation was performed in December 1981. Complete removal of the tumor was impossible because of its unexpected, unusual hardness. The pathologic diagnosis was a malignant mesenchymal tumor, compatible with a malignant nerve sheath tumor of the acoustic nerve. A second operation was performed in January 1982, but the rapid postoperative regrowth of the tumor necessitated a third operation in March 1982. The patient died in the next month. Family histories did not show any evidence of von Recklinghausen's disease, and neither did the patient have any clinical stigmata of this disease.
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PMID:[Malignant schwannoma of acoustic nerve: a case report]. 240 37

Nine duodenal carcinoids from patients with von Recklinghausen's neurofibromatosis (VRNF) were investigated for their morphologic, immunocytochemical, and ultrastructural characteristics, and were compared with seven similar tumors from patients without VRNF. Strong similarities were found between tumors in each group. Irrespective of their association with VRNF, duodenal carcinoids arose in adults and usually produced jaundice, upper intestinal bleeding, or obstruction. Tumors larger than 2.0 cm had already metastasized when first detected. All tumors showed a mixed architectural pattern; five tumors associated with VRNF were of the psammomatous type, as opposed to two of those without VRNF. While no tumors showed argentaffinity, stray argyrophil cells were present only in the three tumors not associated with VRNF. All of the tumors showed immunocytochemical evidence of somatostatinomas, and only one VRNF-associated tumor showed immunoreactivity for an additional regulatory substance, as opposed to three of those not associated with VRNF. Thus, while VRNF-associated duodenal carcinoids are not otherwise distinctive, they tend to be pure somatostatinomas (eight of nine cases), whereas similar tumors unassociated with VRNF are frequently multihormonal (three of seven cases). While many more duodenal carcinoids need to be investigated systematically for their immunocytochemical profile, detection of a pure somatostatinoma in the duodenum should alert one to the possibility of coexistent VRNF.
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PMID:Duodenal carcinoids in patients with and without neurofibromatosis. A comparative study. 242 64

The purely epithelioid malignant peripheral nerve sheath tumor (PNST) is a rare form of PNT possibly first described by McCormack et al. in 1954. This tumor type is distinguishable from the glandular PNT and PNT with differentiated neuroepithelium (medulloepithelioma and neuroepithelioma) and differs from the ordinary epithelioid PNT because of the absence of a spindle cell component typical of malignant PNSTs. The two examples of purely epithelioid malignant PNT we describe arose in the popliteal fossa from the sciatic and tibial nerves of men with no definite evidence of von Recklinghausen's neurofibromatosis. Both tumors were partly mucinous, and so closely mimicked carcinoma and a few non-neurogenic myxoid sarcomas histologically that their final classification depended upon proof of a neural origin.
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PMID:The purely epithelioid malignant peripheral nerve sheath tumor. 242 46

Ninety-two cases of intrathoracic neurogenic tumors operated on between 1950 and 1982 are reviewed. The benign forms (86 cases, 93.5%) included 23 ganglioneuromas, 50 neurilemmomas and 13 neurofibromas. Of the latter, 4 occurred in patients with Von Recklinghausen's disease. A double local recurrence was observed after the removal of a neurilemmoma. One of the patients with generalized neurofibromatosis died 5 months after operation from local sarcomatous degeneration and distant metastases. In this group of benign lesions, no other death was observed which could be attributed to the endothoracic neural tumor. The malignant forms (6 cases, 6.5%) included 4 ganglioneuroblastomas and 2 neurofibrosarcomas. The surgical excisions were described as radical in every case and all the patients were given radiotherapy postoperatively. One patient with ganglioneuroblastoma died from metastases 2 years later, and one with neurofibrosarcoma from local recurrences 7 months later. One patient with neurofibrosarcoma and 3 with ganglioneuroblastomas are alive and well 4, 5, 6 and 11 years, respectively, later. Surgical excision remains the best method of diagnosing and treating endothoracic tumors of neural origin. Of special interest are the "dumbbell" or hourglass tumors and lesions which occur in Von Recklinghausen's disease.
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PMID:Neurogenic intrathoracic tumors. A clinicopathological review of 92 cases. 242 96

Meningioangiomatosis is a rare benign tumor of the central nervous system. Most cases are associated with von Recklinghausen's neurofibromatosis. The case of a 9-year-old boy with a 6-year history of temporal lobe epilepsy is reported. Computerized tomography revealed a hyperdense lesion in the region. The lesion was avascular on angiography. Magnetic resonance imaging showed a large well-demarcated abnormality with hyper- and hypodense regions on T2-weighted images. The abnormality did not extend into the white matter. Histological sections of the biopsy specimen disclosed an organoid transcortical lesion composed of interlacing finger-like fascicles of vascularized fibromeninges. Most fascicles exhibited one or more central slit-like capillaries cuffed by fibroblasts and invaginated meningeal tissue arranged in a parallel or concentric manner. Typical psammoma bodies were evident throughout the lesion, as well as in the intervening, mildly gliotic cerebral cortex. Proliferative meningothelial cells were present in the overlying leptomeninges. The lesion in this case was a hamartoma rather than a neoplasm.
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PMID:Meningioangiomatosis in a patient without von Recklinghausen's disease. Case report. 246 77

This report presents concomitant occurrence of an adrenal ganglioneuroma and a contralateral pheochromocytoma in a patient with von Recklinghausen's disease. The patient's daughter also has cutaneous neurofibromatosis and an adrenal medullary tumor indicating that the observed "three component disease" may represent an inherited neurocristopathy. Immunocytochemically the ganglioneuroma showed a positive reaction with a tyrosinhydroxylase antiserum, but a negative reaction with a dopamine-beta-hydroxylase antiserum, suggesting the capacity of dopamine synthesis. Frequent ganglion cells were immunopositive against neuropeptide Y, but occasional ganglion cells were also positive against enkephalin and substance P. Adrenergic nerve fibers were abundant in the Schwann cell portion of the tumor, but peptide containing nerve cell processes were also demonstrated.
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PMID:Concomitant occurrence of an adrenal ganglioneuroma and a contralateral pheochromocytoma in a patient with von Recklinghausen's neurofibromatosis. An immunocytochemical study. 249 53

Neurofibromatosis type II (NF-II) has been traditionally referred to as "acoustic" neurofibromatosis and is not known to be genetically distinct from classic von Recklinghausen's disease (NF-I). Neurofibromatosis type II is due to a lesion on chromosome 22q, while von Recklinghausen's neurofibromatosis is from a defect on chromosome 17. The approximate incidence of NF-II is one in 50,000, with bilateral acoustic neuromas occurring in over 90% of those with the abnormal gene. We studied a 17-year-old boy with NF-II who presented with bilateral acoustic neuromas and concomitant primary nasopharyngeal meningioma. Less than 30 nasopharyngeal meningiomas have been documented, and the presence of both tumor types in the same individual is unique in the literature.
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PMID:Neurofibromatosis type II of the head and neck. 249 12

Plexiform neurilemmoma (PN) is a rare benign peripheral nerve sheath tumor. The tumor is an uncommon nodular variant of schwannoma. Eleven cases of cutaneous plexiform neurilemmoma (CPN) were studied by clinicopathologic correlation, immunohistochemistry, and electron microscopy. The patients' ages ranged from 6 to 80 yr; the median age was 37 yr. The tumors were presented as single, soft to rubbery, movable, nontender, and sometimes painful nodules ranging from 0.5 cm to 2.5 cm. in diameter. The lesions were most commonly located on the extremities. The overlying skin surface was intact. These tumors were not associated with von Recklinghausen's neurofibromatosis or neurilemmomatosis. On gross examination the cut surface of the tumors showed grayish-white to yellow or tan coloration and had a well-defined border, but there was no evidence of a plexiform growth pattern. The microscopic features were characterized by single or multiple well-circumscribed nodules of spindle-shaped tumor cells. The nuclei were irregular and elongated, and the cytoplasm was eosinophilic and fibrillary without distinct cytoplasmic borders. Nuclear palisading was prominent, and Verocay bodies were present. Mitotic figures were rare (fewer than 2 per 20 high-power fields). Bodian stain showed presence of nerve fibers at the periphery of the tumor. The adjacent tissue showed wavy, spindle-shaped cells and collagen fibers in a myxoid stroma rich in hyaluronic acid, a pattern reminiscent of neurofibroma. The tumor cells showed positive reactivity with anti-S-100 protein in both the nuclei and cytoplasm. Glial fibrillary acid protein was focally positive, and neuron-specific enolase was negative. Electron microscopy displayed features of Schwann cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Solitary cutaneous plexiform neurilemmoma (schwannoma): a clinicopathologic, immunohistochemical, and ultrastructural study of 11 cases. 249 41


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