Endobronchial Manifestation of Methotrexate-induced Lymphoproliferative Disorder.

Lymphoproliferative disorders can occur in patients with autoimmune disorders who undergo long-term methotrexate therapy (MTX-LPD). Although the manifestations of MTX-LPD are diverse, little attention is paid to endobronchial involvement. We herein describe two patients with MTX-LPD who presented with parenchymal pulmonary tumors and endobronchial involvement of LPD; one had lymphomatoid gramulomatosis and the other LPD. The patients had no tumors adjacent to the endobronchial lesions. The endobronchial findings included multiple protruded mucosal lesions covered with white material, which was pathologically consistent with LPD. Recognition of the findings may help in making an earlier diagnosis of MTX-LPD in appropriate settings.