Schwannoma of bone

Summary
Description

Schwannoma, or neurilemmoma, is a rare benign tumor of bone

People and Age
Schwannomas are found at all ages but most commonly between age 20 and 50.
Symptoms and Presentation
Most lesions are asymptomatic.
Brief description of the xray
Radiologically, schwannomas present as well-circumscribed lytic, expansile lesions with sclerotic borders.
Brief desc of tx
Most lesions may be observed without surgery. Curettage is effective for symptomatic or large lesions.
Tumor Name
Tumor Type
Benign or Malignant
Body region
Most Common Bones
Complete Information on this Tumor
Introduction and Definition

Schwannoma, or neurilemmoma, is a rare benign tumor of bone. It accounts for less than 0.1%1 of all bone neoplasms. It occurs most often in the head, neck, and flexor surfaces of upper and lower extremities.

Incidence and Demographics
Schwannomas are found at all ages but most commonly between age 20 and 50.
Symptoms and Presentation

Most lesions are asymptomatic.

X-Ray Appearance and Advanced Imaging Findings
Radiologically, schwannomas present as well-circumscribed lytic, expansile lesions with sclerotic borders.
Laboratory Findings
On gross examination, a schwannoma as is a soft pink to yellow encapsulated mass less than five centimeters in size. The lesion may have cysts or calcification.
Histopathology findings
Histologically, schwannomas have two distinct components. The Antoni A regions are highly ordered and cellular with spindle shaped Schwann cells that have poorly defined eosinophilic cytoplasm and basophilic nuclei. Verocan,T bodies are configurations of palisading cells that alternate with acellular eosinophilic areas. The Antoni B regions are much less cellular and are characterized by large thin walled vessels surrounded edematous stroma. Schwannomas stain positive for S100 and vimentin.
Treatment Options for this Tumor
Most lesions may be observed without surgery. Curettage is effective for symptomatic or large lesions.
Suggested Reading and Reference
1 Huvos, Andrew, Bone Tumors:Diagnosis. Treatment and Prognosis, W.B. Saunders, Co., 1991.

Fletcher, Christopher, Diagnostic Histopathology of Tumors, Churchill Livingstone, 1995.
1/22/98