CTLA4 and metastatic melanoma: The cost-effectiveness simulation of treatment in BRAF-V600 mutant metastatic melanoma suggests starting treatment with anti-programmed cell death protein 1 (PD-1) plus anti- cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is more cost-effective than starting with targeted therapy (or anti-PD-1 monotherapy) [5].