With a background in both immunology and cancer biology, I’ve always had a fascination with the interplay between the body’s immune system and any tumors that might pop up. Originally, it made sense that the immune system would actively seek out and destroy cancerous cells, but the emerging consensus is that the interactions between cancers and host immunity is far more complex. In addition to growing new blood vessels and reprogramming metabolic processes, there appears to be some imbalance between avoiding immune cells while also promoting tumor-infiltrating inflammatory cells to promote its growth. ¹ (Figure 1) Trying to dissect this apparent contradictory relationship between tumors and host immunity remains a hot topic.