thymoma-associated multiorgan autoimmunity thymoma-associated multiorgan autoimmunity thymoma-associated multiorgan autoimmunity (tama) is a severe often fatal disease that presents in some patients with thymoma. it has also been referred to in the medical literature as "thymoma-associated graft-versus-host-like disease". thymoma-associated multiorgan autoimmunity (tama) presentation patients with tama present with variable combinations of a morbilliform skin eruption, chronic diarrhea, and abnormal liver enzymes. the histopathology of the skin, liver, or bowel mucosa resembles gvhd. pathophysiology thymoma is a common neoplasm arising from the thymus, the primary lymphoid organ where t cells become educated to distinguish "self" from "non self". in the setting of thymoma, abnormal thymic education occurs as a result of subtle differences in antigen processing. in tama these differences result in autoreactive t cells escaping from the thymus. this results in a condition similar to graft-versus-host disease. diagnosis treatment patients often have a refractory disease course but some patients may respond to phototherapy. history this disease name was coined by emanual maverakis and described in detail in 2007 but case reports of graft-versus-host-like disease in the setting of thymoma date back to at least the mid 1990s.