Ipilimumab immune-related adverse reactions: a case report.

Ipilimumab is an immunomodulating agent approved by the Food and Drug Administration (FDA) as of March 2011 for the treatment of metastatic melanoma. The medication works by inhibiting cytotoxic T-lymphocyte antigen 4, which typically works to down-regulate the T-cell response and protects self-antigens from recognition by the immune system. Since the T-cells are no longer down-regulated by this antigen, they are allowed to proliferate, thereby helping to prevent melanoma tumor evasion. As a result of the up-regulation of the immune system, numerous immune-mediated adverse effects have been reported including colitis, dermatitis, hepatitis and rarely hypophysitis. Typically, these effects are treated with high-dose steroids and most eventually resolve. We present a case of autoimmune (lymphocytic) hypophysitis following treatment with four doses of ipilimumab 3mg/kg and discuss the work-up, treatment and prognosis of the event.