Neural tumors

Chapter 22


Neural tumors




Neurofibroma



Neurofibromas may occur as solitary lesions. Multiple widespread neurofibromas characterize neurofibromatosis (von Recklinghausen’s disease) in which they are seen in association with café-au-lait macules, axillary freckling, and pigmented hamartomas of the iris (Lisch nodules).







Schwannoma (neurilemmoma)







Psammomatous melanotic schwannoma is a variant with psammoma bodies and melanin. It is associated with Carney’s complex (myxomas, spotty pigmentation, and endocrinopathy).




Neuromas


Neuromas are nerve sheath tumors with a roughly 1 : 1 ratio of axons to Schwann cells.





Palisaded encapsulated neuroma



Palisaded encapsulated neuromas are solitary painless papules that occur most commonly on the lower central face. The name is somewhat of a misnomer, as there is usually no palisading and only an inconspicuous capsule. Histologically, they resemble the mucosal neuromas of multiple endocrine neoplasia syndrome type 2b, an autosomal-dominant syndrome caused by a mutation of the RET proto-oncogene. In addition to the multiple mucosal neuromas, the syndrome is characterized by a marfanoid habitus, medullary carcinoma of the thyroid, pheochromocytoma, and hyperparathyroidism.


Apr 26, 2016 | Posted by in Dermatology | Comments Off on Neural tumors
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