Progressive multifocal leukoencephalopathy associated with thymoma with immunodeficiency: a case report and literature review.

It is necessary to consider the possibility of immunodeficiency due to GS in patients with PML related to thymoma. Neurologists should keep in mind the risk of PML in MG patients with thymoma, even if the MG symptoms are in remission, and should thus evaluate the immunological status of the patient accordingly.