Methotrexate-Associated Lymphoproliferative Disorder in the Nasopharynx: A Case Report

Methotrexate (MTX) is widely used in the treatment of autoimmune diseases, including Crohn's disease, but may be associated with the development of MTX-associated lymphoproliferative disorder (MTX-LPD).Although MTX-LPD frequently involves extranodal sites, involvement of the nasopharynx is rare.We report a case of MTX-LPD involving the nasopharynx in a 19-year-old male with Crohn's disease.The patient presented with right ear fullness, and endoscopic examination revealed a large polypoid mass in the nasopharynx.Imaging demonstrated a symmetric striated lesion suggestive of adenoid hypertrophy; however, lymphoma could not be excluded.Histopathologic evaluation confirmed MTX-LPD.Following the discontinuation of MTX, the lesion showed gradual regression without additional therapy, and the patient's symptoms were completely resolved.This case highlights that MTX-LPD may mimic benign lymphoid hypertrophy in the nasopharynx, and emphasizes the importance of histologic confirmation in immunosuppressed patients, as withdrawal of MTX alone may lead to spontaneous regression and help avoid unnecessary aggressive treatment.