A 24-year-old female rheumatoid arthritis (RA) patient, who once attained complete remission (CR) with the combination therapy with tumor necrosis factor alpha (TNF-alpha) inhibitor adalimumab (ADA) and methotrexate (MTX), showed the occurrence of Epstain- Barr virus (EBV)-associated lymphoproliferative disorder (LPD). The gene discussed is TNF; the disease is lymphoproliferative syndrome.