Whole body toxicity, measured by weight change, was recorded for both models (MC38/CEA and E0771/CEA results shown in Figure 2A; Figure S4A, respectively), which indicated that the MC38/CEA tumor bearing male mice are more sensitive to IL‐2‐Fc treatment than E0771/CEA tumor bearing female mice due to higher weight loss seen in Figure 2A. Here, IL2 is linked to neoplasm.