Adalimumab, a fully human anti-TNFα monoclonal antibody, has been shown to be effective and generally well tolerated when used for both induction and maintenance therapy for CD.5 In addition, the sustained benefits of long-term use of adalimumab in clinical practice have been confirmed by the results of both Western6 and Japanese studies.7 However, evidence from large-scale population-based studies involving Japanese patients receiving adalimumab in clinical practice remains insufficient. Here, TNF is linked to Cowden disease.