A Rare but Morbid Occurrence: Development of Glioblastoma Multiforme During Tumor Necrosis Factor Inhibitor Therapy.

The use of biologic therapies continues to become more prevalent in the treatment of inflammatory bowel disease, particularly for more severe disease. Although generally safe and effective, specific biologic classes such as tumor necrosis factor inhibitor (anti-TNF) medications are known to increase the risk of certain cancers. Glioblastoma multiforme (GBM) is an aggressive brain tumor which tends to arise sporadically but may be associated with anti-TNF therapies. Here, we present a case of a 69-year-old male with Crohn's disease who developed GBM while on adalimumab therapy. This case report highlights the potential rare association between GBM and anti-TNF therapy and further discusses the difficulty of managing active Crohn's disease with concomitant GBM, specifically the difficulty encountered in managing a disease flare.