Myasthenia gravis, an autoimmune manifestation of lymphoma and lymphoproliferative disorders: case reports and review of literature.

Myasthenia gravis (MG) is an autoimmune disease mediated by antibodies to acetylcholine receptors (AChRs) or muscle specific tyrosine kinase (MuSK). While the frequent association of MG with thymoma in patients aged 40-60 years is well recognized, its occurrence in patients with lymphoma has not been well studied. We review the literature on the association of MG and lymphoid malignancies and report two new patients. MG can occur in a synchronous or non-synchronous fashion with lymphoma. The pathogenesis of MG in lymphoid malignancies is probably heterogeneous and likely relates to perturbations in the immune mechanisms that normally prevent the emergence of autoimmunity. These perturbations could be the result of the lymphoid malignancy per se, or its treatment.