Ibrutinib treatment of mantle cell lymphoma complicated by progressive multifocal leukoencephalopathy

This case report demonstrates a possible severe adverse effect of the immunomodulatory drug ibrutinib and the importance of a multidisciplinary approach in its diagnosis. Since PML is a rare but highly fatal disease, it is of utmost importance to be aware of the possible connection with the use of this drug to prevent missed or delayed diagnosis, considering that timely therapeutic intervention is crucial for improved prognosis.