Thymoma-associated multiorgan autoimmunity (TAMA) is a severe often fatal disease that presents in some patients with thymoma.

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.

[2] 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.