Thymoma is a rare type of cancer in which tumors form on the outside surface of the thymus, a small organ that lies in the upper chest under the breastbone and is part of the lymphatic system.

Thymoma is commonly associated with myasthenia gravis, a neuromuscular disorder in which antibodies destroy the link between muscle and nerves, causing skeletal muscle weakness.

Doctors in the GW Cancer Center’s Neuro Oncology Program typically use minimally invasive robotic surgery to treat thymoma, which affects approximately 400 people in the U.S. each year.