Abstract
Plasmablastic lymphoma (PBL) is a rare and aggressive B-cell lymphoma with a poor prognosis and is typically linked to human immunodeficiency virus (HIV)-related immunodeficiency. PBL associated with ulcerative colitis (UC) is an extremely rare condition. We report the case of a 63-year-old HIV-negative woman with UC who developed colonic PBL after long-term mesalazine and budesonide treatment. She achieved complete remission following chemotherapy and abdominal radiotherapy, with no recurrence for more than three years. To our knowledge, this is the fourth reported case of UC-associated PBL and demonstrates the longest survival. Chemoradiotherapy may be an effective treatment for localized PBL.