Which disease is commonly associated with thymoma?

Which disease is commonly associated with thymoma?

• A. Lambert-Eaton syndrome
• B. Guillain-Barré syndrome
• C. Multiple sclerosis
• D. Myasthenia gravis

Answer: (D)

Thymic tumors highlight how the thymus controls T cell tolerance. A thymoma can disrupt this process, allowing autoreactive T cells to help B cells produce antibodies against nicotinic acetylcholine receptors at the motor end plate. This autoimmune attack reduces functional receptors, impairing neuromuscular transmission and producing fatigable weakness that worsens with use and improves with rest—classic features of myasthenia gravis. Because MG is commonly linked to thymic abnormalities, including thymoma, it is the disease most associated with a thymoma. The other conditions listed are not characteristically connected to thymic tumors: Lambert-Eaton syndrome involves antibodies against presynaptic calcium channels and is usually linked to small cell lung cancer; Guillain-Barré syndrome is a postinfectious demyelinating neuropathy; multiple sclerosis is a CNS demyelinating autoimmune disease.

Thymic tumors highlight how the thymus controls T cell tolerance. A thymoma can disrupt this process, allowing autoreactive T cells to help B cells produce antibodies against nicotinic acetylcholine receptors at the motor end plate. This autoimmune attack reduces functional receptors, impairing neuromuscular transmission and producing fatigable weakness that worsens with use and improves with rest—classic features of myasthenia gravis. Because MG is commonly linked to thymic abnormalities, including thymoma, it is the disease most associated with a thymoma. The other conditions listed are not characteristically connected to thymic tumors: Lambert-Eaton syndrome involves antibodies against presynaptic calcium channels and is usually linked to small cell lung cancer; Guillain-Barré syndrome is a postinfectious demyelinating neuropathy; multiple sclerosis is a CNS demyelinating autoimmune disease.