Neurofibromas

NF-1 Codes for a protein that inhibits the Neurofibroma, leukemia, and pheochromocytoma... 

Eisenbarth, I., Beyer, K., Krone, W. and Assum, G. Toward a survey of somatic mutation of the NF1 gene in benign neurofibromas of patients with neurofibromatosis type 1. Am. J. Hum. Genet. 66 393MT1, 2000. 

Recently, NGF has been shown to cause a significant proliferation of connective tissue mast cells when injected subcutaneously into newborn (day 1) rats [122]. This effect of NGF is blocked by DSCG, which suggests that products released from NGF-stimulated mast cells are responsible (directly or indirectly) for the proliferation or recruitment of other mast cells. In adult rats, a similar proliferation of mucosal mast cells in the small intestine is known to accompany an infection by intestinal nematode, N. brasilensis [123] and has also been reported to accompany the repeated injections of compound 48/80 [ 124], It may be relevant in this regard that mast cells are frequently prominent in a wide variety of fibrotic conditions such as neurofibromatosis where itching around the growing neurofibroma is a common symptom [125]. Treatment of neurofibromatosis with ketotifen, a mast cell stabilizer similar to DSCG, results... 

In November 2005, a phase II/III study in NSCLC patients started in Australia and Canada, hi February 2006, Cediranib was undergoing a UK phase II/III trials in colorectal cancer. At that time, US phase II trials were underway in patients with advanced solid tumors, mesothelioma, melanoma, fiver, ovarian, peritoneal, fallopian tube, kidney, and breast cancers, hi May 2006, a US phase II trial began for neurofibromatosis type I and plexiform neurofibroma. 

Among the symptoms seen in patients with type I NF are hyperpigmented skin lesions (cafe-au-lait spots), benign skin tumors (neurofibromas), dysplasia of the sphenoid bone, and benign tumors of the iris (hamartomas or Lisch nodules). 

Several members of a family have type I neurofibromatosis in which DNA analysis indicates that a son and daughter have inherited the disease from their father. The 16-year-old daughter has a pelvic neurofibroma, her brother exhibits only cafd-au-lait spots and a hamartoma, while the father has no detectable symptoms. 

I. Observe in the patient Cushing s, acromegaly, hyper-hypothyroid, neurofibromas, web neck, short 4th metacarpal, cafe-au-lait spots, swollen feet ... 

Tetraethyl- c8h20nci Y. Non-specific Neurofibromas peripheral nerve sheath tumor cell... 

Acoustic neurofibroma Acute myeloid leukemia (AML) Astrocytoma, high grade Bladder carcinoma Breast carcinoma Colon carcinoma Lung carcinoma, small cell Lung carcinoma, other Melanoma (standard and uveal) Meningioma... 

The perineurial cells in neurofibroma contain EMA, which may be detected immunohistochemically in a small population of cells in these tumors. EMA may also be of some value in the diagnosis of nerve sheath myxoma because of the existence of perineurial elements around most tumor lobules. Nerve sheath neoplasms are occasionally labeled by antibodies to GFAP, as are 50% of soft tissue myoepitheliomas, whereas other benign soft tissue tumors are not. Myelin basic protein may also be of some value in the diagnosis of schwann-ian tumors, although there has been some disagreement in the literature on this point. 

Neurotized melanocytic nevi may be distinguished from neurofibroma factor Xllla is found in neurofibroma, not in melanocytic nevi. 

Leiomyosarcomas are most commonly found in the retroperitoneum in adults. They uncommonly occur in the deep soft tissues of the extremities but may be seen in more superficial sites, particularly in the dermis and subcutis. The differential diagnosis of LMS traditionally includes other sarcomas composed of intersecting spindle-cell fascicles, including fibrosarcoma, MPNST, synovial sarcoma, and spindle cell rhabdomyosarcoma. Additional conditions such as IMT (inflammatory pseudotumor), neurofibroma, and hemangiopericytoma (see Fig. 4.5) are also considerations. 

Kawahara E, Oda Y, Ooi A, et al. Expression of glial fibrillary acidic protein (GFAP) in peripheral nerve sheath tumors A comparative study of immunoreactivity of GFAP, vimentin, SlOO protein, and neurofilament in 38 schwannomas and 18 neurofibromas. Am J Surg Pathol. 1988 12 115-120. 

Fetsch JF, Michal M, Miettinen M. Pigmented (melanotic) neurofibroma A clinicopathologic and immunohistochemical analysis of 19 lesions from 17 patients. Am J Surg Pathol. 2000 24 331-343. 

Fine SW, McClain SA, Li M. Immunohistochemical staining for calretinin is useful for differentiating schwannomas from neurofibromas. Am J Clin Pathol. 2004 122 552-559. 

Schwann-cell neoplasms (peripheral nerve sheath tumors PNST) are usually subdivided into specific neurofibromas and neurilemmomas (schwannomas) because of their differing associations with von Recklinghausen disease and the risk of malignant transformation. They also must be separated from ganglioneuromas. All of these proliferations are reactive for vimentin and... 

The most common cutaneous nerve sheath tumors are neurofibromas often, such tumors are multiple and occur in the setting of von Recklinghausen s neurofibromatosis. Neurilemmomas (schwannomas), granular cell tumors, perineuriomas, and neurothekeomas are represented in the skin as well. ° In contrast, malignant cutaneous peripheral nerve sheath tumors are... 

Detection of the latter three markers, alone or in combination, provides for the reliable identification of PNSTs if all myogenous and epithelial determinants are concurrently absent. In particular, neurilemmoma essentially always shows diffuse and intense reactivity for S-100 protein, but neurofibromas are more heterogeneous immunohistologically. Other determinants also have been detected in selected PNSTs including glial fibrillary acidic protein, neuron-specific enolase, and nerve growth factor receptor. 

S-100 protein, CD56, or CD57. GCT also shares with neurofibroma (but not neurilemmoma) the expression of factor Xnia, and it is also potentially reactive for protein gene product 9.5, calretinin, and inhibin (Fig. 

Cranuiar ceii tumors and neurofibromas factor Xiiia-i-, cairetinin-r, inhibin-r... 

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