Certified Hand Therapist (CHT) Practice Exam

Which rare tumor is associated with the myelin sheath of a nerve?

1. Xanthoma

2. Schwannoma

3. Glomus tumor

4. Inclusion cyst

The correct answer is: Schwannoma

Schwannoma is a tumor that originates from Schwann cells, which are responsible for the formation of the myelin sheath around peripheral nerves. This tumor typically arises on the nerve itself and can occur anywhere along the nerve pathways in the body. These tumors are often characterized by encapsulated structures and can cause symptoms depending on their location, such as pain or neurological deficits due to pressure on the surrounding tissues. The association with the myelin sheath is critical because it highlights the origin of the tumor from the components that protect and insulate nerve fibers. Understanding this connection is essential for recognizing the nature of Schwannomas, their clinical presentation, and the need for appropriate management. In contrast, xanthoma, glomus tumor, and inclusion cysts do not derive from the myelin sheath or involve Schwann cells. Xanthomas are lipid deposits typically associated with various metabolic disorders, glomus tumors arise from the vascular glomus bodies, and inclusion cysts are often remnants of epithelial cells. Therefore, their association with nerve sheaths is unrelated to the pathology observed in Schwannomas.