Minimally invasive thymoma with extensive intravascular growth

A 70-year-old male with grossly non-invasive thymic tumor associated with m yasthenia gravis was subjected to thymothymectomy. Microscopic examination showed extensive intravascular tumor extensions into veins of thymic tissue and surrounding muscles and a minute direct invasion of the thymic tissue. Histologically, the tumor showed mixed-type thymoma with polygonal epithel ial cells. These pathological findings indicated that the tumor cells exten ded mainly into vessels beyond the tumor capsule via tumor drainage veins r ather than invading neighboring structures, After chemotherapy and mediasti nal irradiation, the patient is now in complete remission of myasthenia gra vis and is recurrence-free 15 months after surgery.