Progressive multifocal leukoencephalopathy, a possible complication in a patient with bladder cancer

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the brain, caused by reactivation of the polyomavirus JC (JCV). PML has classically been described in individuals with profound cellular immunosuppression such as patients with AIDS, hematological malignancies, organ transplant recipients or those treated with immunosuppressive or immunomodulatory medications. The occurrence of PML in patients without identifiable immunodeficiency represents a therapeutic challenge. Tumor-induced immune suppression is a fundamental problem in cancer biology. We present a case of 71-year-old man with bladder cancer. The patient was diagnosed with PML after an epileptic seizure followed by a coma. MRI images were compatible with PML. Presence of JC virus in the cerebrospinal fluid confirmed the diagnosis. Unfortunately the patient died shortly after the diagnosis. There is no specific treatment for JCV. The reconstitution of the immune system seems the most effective approach.