CTLA4 and lymphoma: While agents targeting T cell immunity such as antibodies against cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), programmed death-1 (PD-1) and its ligand (PD-L1) have been highly effective in certain solid tumors and lymphoma subtypes, their efficacy in other hematologic malignancies has been limited [1–7].