CTLA4-induced splenomegaly and a review of the literature pertaining to autoimmune complications of therapy.

CTLA4-blocking antibodies induce tumor regression in a subset of patients with metastatic melanoma by optimizing T-cell activity to fight the malignant cells. In addition to therapeutic benefits, CTLA4 therapy may induce immune-related adverse events (irAE). Studies on CTLA4 knockout and other CTLA4 deficient mice have resulted in splenomegaly, lymphoproliferation and fatal multi-organ destruction. The authors present a case of a 68-year-old patient who has developed splenomegaly following CTLA4 therapy. CTLA4 therapy's risks and benefits should be weighed carefully in the treatment of malignant melanoma. Larger prospective multi-center trials are needed to gauge the efficacy and complication rate of CTLA4 therapy. The authors propose that patients should get short-term surveillance imaging (CT or PET/CT) to exclude the multiple abdominopelvic complications and quickly terminate therapy if clinically warranted. It is also necessary for clinicians to carefully monitor for the number of possible complications associated with this immunotherapy.