Introduction A benign encapsulated tumor composed of Schwann cells tumor is well encapsulated on the surface of a peripheral nerve also known as Schwannoma Age & location peak incidence is in the 3rd to 6th decades previous test question ages: 40, 45 affect males and females equally often occurs on flexor surfaces of extremities and head and neck larger lesions may occur in the pelvis Pathoanatomy can affect motor or sensory nerves Genetics often associated with mutations affecting NF2 gene Malignant transformation extremely rare Presentation Symptoms usually asymptomatic may have paresthesia in the distribution of the peripheral nerve Physical exam may have positive Tinel’s sign in the distribution of the nerve affected may be present Imaging MRI sequences low intensity (dark) T1 high intensity (bright) on T2 diffuse enhancement with gadolinium findings may show “string sign” difficult to differentiate from neurofibroma Histology Gross pathology the lesion is well encapsulated in a nerve sheath gray in color Histology Antoni A structure a pattern of spindle cells arranged in intersecting bundles (spindle cell battle formation) Antoni B areas with less cellularity with loosely arranged cells Verocay bodies pathognomonic composed of two rows of aligned nuclei in a palisading formation Immunochemistry strongly uniform S100 antibody staining Treatment Nonoperative observation indications asymptomatic lesions Operative marginal excision indications symptoms or interfering with quality of life technique nerve function may be preserved by careful dissection, excising the lesion parallel to the nerve fascicles so the lesion may be extruded. complications small risk of sensory deficits outcomes recurrence is rare
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All Videos (1) Podcasts (0) Login to View Community Videos Login to View Community Videos Cervical Cord Neurilemmoma - Left C7 root Pathology - Neurilemmoma D 10/15/2012 184 views 5.0 (1)